Add comment to matching #endif

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 8daa267..b5ad445 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -1332,7 +1332,7 @@
 #define MBEDTLS_DEPRECATED      __attribute__((deprecated))
 #else
 #define MBEDTLS_DEPRECATED
-#endif
+#endif /* MBEDTLS_DEPRECATED_WARNING */
 
 MBEDTLS_DEPRECATED extern int (*mbedtls_ssl_hw_record_init)(
                     mbedtls_ssl_context *ssl,