Fix warning in reduced config
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b608e5c..6462ad0 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1103,6 +1103,11 @@
     }
 #endif
 
+    /* Unused if AEAD is the only option */
+    ((void) ssl);
+    ((void) session);
+    ((void) mode);
+
     return( MAC_NONE );
 }