Update documentation references to the AEAD macros

Where a change was necessary, the new documentation was copied from the
PSA Crypto API spec exactly, with the exception of PSA_AEAD_TAG_LENGTH,
which needed some adjustment.

Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index 81e1f28..98de335 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -2113,9 +2113,16 @@
  *                                authentication tag is appended to the
  *                                encrypted data.
  * \param ciphertext_size         Size of the \p ciphertext buffer in bytes.
- *                                This must be at least
- *                                #PSA_AEAD_ENCRYPT_OUTPUT_SIZE(\p alg,
- *                                \p plaintext_length).
+ *                                This must be appropriate for the selected
+ *                                algorithm and key:
+ *                                - A sufficient output size is
+ *                                  #PSA_AEAD_ENCRYPT_OUTPUT_SIZE(\c key_type,
+ *                                  \p alg, \p plaintext_length) where
+ *                                  \c key_type is the type of \p key.
+ *                                - #PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(\p
+ *                                  plaintext_length) evaluates to the maximum
+ *                                  ciphertext size of any supported AEAD
+ *                                  encryption.
  * \param[out] ciphertext_length  On success, the size of the output
  *                                in the \p ciphertext buffer.
  *
@@ -2173,9 +2180,16 @@
  * \param ciphertext_length       Size of \p ciphertext in bytes.
  * \param[out] plaintext          Output buffer for the decrypted data.
  * \param plaintext_size          Size of the \p plaintext buffer in bytes.
- *                                This must be at least
- *                                #PSA_AEAD_DECRYPT_OUTPUT_SIZE(\p alg,
- *                                \p ciphertext_length).
+ *                                This must be appropriate for the selected
+ *                                algorithm and key:
+ *                                - A sufficient output size is
+ *                                  #PSA_AEAD_DECRYPT_OUTPUT_SIZE(\c key_type,
+ *                                  \p alg, \p ciphertext_length) where
+ *                                  \c key_type is the type of \p key.
+ *                                - #PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(\p
+ *                                  ciphertext_length) evaluates to the maximum
+ *                                  plaintext size of any supported AEAD
+ *                                  decryption.
  * \param[out] plaintext_length   On success, the size of the output
  *                                in the \p plaintext buffer.
  *
@@ -2612,10 +2626,18 @@
  * \param input_length          Size of the \p input buffer in bytes.
  * \param[out] output           Buffer where the output is to be written.
  * \param output_size           Size of the \p output buffer in bytes.
- *                              This must be at least
- *                              #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c alg,
- *                              \p input_length) where \c alg is the
- *                              algorithm that is being calculated.
+ *                              This must be appropriate for the selected
+ *                                algorithm and key:
+ *                                - A sufficient output size is
+ *                                  #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c key_type,
+ *                                  \c alg, \p input_length) where
+ *                                  \c key_type is the type of key and \c alg is
+ *                                  the algorithm that were used to set up the
+ *                                  operation.
+ *                                - #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p
+ *                                  input_length) evaluates to the maximum
+ *                                  output size of any supported AEAD
+ *                                  algorithm.
  * \param[out] output_length    On success, the number of bytes
  *                              that make up the returned output.
  *
@@ -2626,9 +2648,9 @@
  *         set, and have lengths set if required by the algorithm).
  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
  *         The size of the \p output buffer is too small.
- *         You can determine a sufficient buffer size by calling
- *         #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c alg, \p input_length)
- *         where \c alg is the algorithm that is being calculated.
+ *         #PSA_AEAD_UPDATE_OUTPUT_SIZE(\c key_type, \c alg, \p input_length) or
+ *         #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p input_length) can be used to
+ *         determine the required buffer size.
  * \retval #PSA_ERROR_INVALID_ARGUMENT
  *         The total length of input to psa_aead_update_ad() so far is
  *         less than the additional data length that was previously
@@ -2665,9 +2687,7 @@
  * This function has two output buffers:
  * - \p ciphertext contains trailing ciphertext that was buffered from
  *   preceding calls to psa_aead_update().
- * - \p tag contains the authentication tag. Its length is always
- *   #PSA_AEAD_TAG_LENGTH(\c alg) where \c alg is the AEAD algorithm
- *   that the operation performs.
+ * - \p tag contains the authentication tag.
  *
  * When this function returns successfuly, the operation becomes inactive.
  * If this function returns an error status, the operation enters an error
@@ -2677,18 +2697,32 @@
  * \param[out] ciphertext       Buffer where the last part of the ciphertext
  *                              is to be written.
  * \param ciphertext_size       Size of the \p ciphertext buffer in bytes.
- *                              This must be at least
- *                              #PSA_AEAD_FINISH_OUTPUT_SIZE(\c alg) where
- *                              \c alg is the algorithm that is being
- *                              calculated.
+ *                              This must be appropriate for the selected
+ *                              algorithm and key:
+ *                              - A sufficient output size is
+ *                                #PSA_AEAD_FINISH_OUTPUT_SIZE(\c key_type,
+ *                                \c alg) where \c key_type is the type of key
+ *                                and \c alg is the algorithm that were used to
+ *                                set up the operation.
+ *                              - #PSA_AEAD_FINISH_OUTPUT_MAX_SIZE evaluates to
+ *                                the maximum output size of any supported AEAD
+ *                                algorithm.
  * \param[out] ciphertext_length On success, the number of bytes of
  *                              returned ciphertext.
  * \param[out] tag              Buffer where the authentication tag is
  *                              to be written.
  * \param tag_size              Size of the \p tag buffer in bytes.
- *                              This must be at least
- *                              #PSA_AEAD_TAG_LENGTH(\c alg) where \c alg is
- *                              the algorithm that is being calculated.
+ *                              This must be appropriate for the selected
+ *                              algorithm and key:
+ *                              - The exact tag size is #PSA_AEAD_TAG_LENGTH(\c
+ *                                key_type, \c key_bits, \c alg) where
+ *                                \c key_type and \c key_bits are the type and
+ *                                bit-size of the key, and \c alg is the
+ *                                algorithm that were used in the call to
+ *                                psa_aead_encrypt_setup().
+ *                              - #PSA_AEAD_TAG_MAX_SIZE evaluates to the
+ *                                maximum tag size of any supported AEAD
+ *                                algorithm.
  * \param[out] tag_length       On success, the number of bytes
  *                              that make up the returned tag.
  *
@@ -2699,11 +2733,11 @@
  *         operation with a nonce set).
  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
  *         The size of the \p ciphertext or \p tag buffer is too small.
- *         You can determine a sufficient buffer size for \p ciphertext by
- *         calling #PSA_AEAD_FINISH_OUTPUT_SIZE(\c alg)
- *         where \c alg is the algorithm that is being calculated.
- *         You can determine a sufficient buffer size for \p tag by
- *         calling #PSA_AEAD_TAG_LENGTH(\c alg).
+ *         #PSA_AEAD_FINISH_OUTPUT_SIZE(\c key_type, \c alg) or
+ *         #PSA_AEAD_FINISH_OUTPUT_MAX_SIZE can be used to determine the
+ *         required \p ciphertext buffer size. #PSA_AEAD_TAG_LENGTH(\c key_type,
+ *         \c key_bits, \c alg) or #PSA_AEAD_TAG_MAX_SIZE can be used to
+ *         determine the required \p tag buffer size.
  * \retval #PSA_ERROR_INVALID_ARGUMENT
  *         The total length of input to psa_aead_update_ad() so far is
  *         less than the additional data length that was previously
@@ -2762,10 +2796,15 @@
  *                              that could not be processed until the end
  *                              of the input.
  * \param plaintext_size        Size of the \p plaintext buffer in bytes.
- *                              This must be at least
- *                              #PSA_AEAD_VERIFY_OUTPUT_SIZE(\c alg) where
- *                              \c alg is the algorithm that is being
- *                              calculated.
+ *                              This must be appropriate for the selected algorithm and key:
+ *                              - A sufficient output size is
+ *                                #PSA_AEAD_VERIFY_OUTPUT_SIZE(\c key_type,
+ *                                \c alg) where \c key_type is the type of key
+ *                                and \c alg is the algorithm that were used to
+ *                                set up the operation.
+ *                              - #PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE evaluates to
+ *                                the maximum output size of any supported AEAD
+ *                                algorithm.
  * \param[out] plaintext_length On success, the number of bytes of
  *                              returned plaintext.
  * \param[in] tag               Buffer containing the authentication tag.
@@ -2781,9 +2820,9 @@
  *         operation with a nonce set).
  * \retval #PSA_ERROR_BUFFER_TOO_SMALL
  *         The size of the \p plaintext buffer is too small.
- *         You can determine a sufficient buffer size for \p plaintext by
- *         calling #PSA_AEAD_VERIFY_OUTPUT_SIZE(\c alg)
- *         where \c alg is the algorithm that is being calculated.
+ *         #PSA_AEAD_VERIFY_OUTPUT_SIZE(\c key_type, \c alg) or
+ *         #PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE can be used to determine the
+ *         required buffer size.
  * \retval #PSA_ERROR_INVALID_ARGUMENT
  *         The total length of input to psa_aead_update_ad() so far is
  *         less than the additional data length that was previously