Use stdint.h types in multipart AEAD functions

No implementation yet.
diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index fb9424a..4226587 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -2319,7 +2319,7 @@
  * \retval #PSA_ERROR_CORRUPTION_DETECTED
  */
 psa_status_t psa_aead_generate_nonce(psa_aead_operation_t *operation,
-                                     unsigned char *nonce,
+                                     uint8_t *nonce,
                                      size_t nonce_size,
                                      size_t *nonce_length);
 
@@ -2353,7 +2353,7 @@
  * \retval #PSA_ERROR_CORRUPTION_DETECTED
  */
 psa_status_t psa_aead_set_nonce(psa_aead_operation_t *operation,
-                                const unsigned char *nonce,
+                                const uint8_t *nonce,
                                 size_t nonce_length);
 
 /** Declare the lengths of the message and additional data for AEAD.
@@ -2507,7 +2507,7 @@
 psa_status_t psa_aead_update(psa_aead_operation_t *operation,
                              const uint8_t *input,
                              size_t input_length,
-                             unsigned char *output,
+                             uint8_t *output,
                              size_t output_size,
                              size_t *output_length);