Fixed compile warning (in test-ref-configs)
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index bdd2d95..fe2103b 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -236,6 +236,8 @@
     const ecp_curve_info *info;
 #if defined(POLARSSL_SSL_SET_CURVES)
     const ecp_group_id *grp_id;
+#else
+    ((void) ssl);
 #endif
 
     *olen = 0;