style + missing cast

Signed-off-by: Johan Pascal <johan.pascal@belledonne-communications.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index a6b8f1b..840722d 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -3232,6 +3232,7 @@
  *                          of the SSL configuration structure.
  *                          The list must not hold more than
  *                          MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
+ *                          (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
  *
  * \return                  0 on success
  * \return                  #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of