doc improvement in aes include

Remove description of non-existing "mode" parameter from the docs of mbedtls_aes_crypt_ctr

Backport of #5105

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/include/mbedtls/aes.h b/include/mbedtls/aes.h
index 33a11a7..dc5ae19 100644
--- a/include/mbedtls/aes.h
+++ b/include/mbedtls/aes.h
@@ -538,10 +538,6 @@
  * \brief      This function performs an AES-CTR encryption or decryption
  *             operation.
  *
- *             This function performs the operation defined in the \p mode
- *             parameter (encrypt/decrypt), on the input data buffer
- *             defined in the \p input parameter.
- *
  *             Due to the nature of CTR, you must use the same key schedule
  *             for both encryption and decryption operations. Therefore, you
  *             must use the context initialized with mbedtls_aes_setkey_enc()