Comply with mbedtls naming rules

Signed-off-by: Johan Pascal <johan.pascal@belledonne-communications.com>
diff --git a/library/version_features.c b/library/version_features.c
index 62b0553..42ccaf9 100644
--- a/library/version_features.c
+++ b/library/version_features.c
@@ -534,6 +534,9 @@
 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY)
     "MBEDTLS_SSL_DTLS_HELLO_VERIFY",
 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    "MBEDTLS_SSL_DTLS_SRTP",
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
 #if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE)
     "MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE",
 #endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE */