Pass more args to custom TLS init

src/tls_openssl.c

@@ -28,7 +28,8 @@ void mg_tls_init(struct mg_connection *c, struct mg_tls_opts *opts) {
   if (tls == NULL) {
     mg_error(c, "TLS OOM");
     goto fail;
-  } else if (opts->ifn != NULL && opts->ifn(opts) != 0) {
+  } else if (opts->custom_init != NULL &&
+             opts->custom_init(c, opts, tls) != 0) {
     mg_error(c, "TLS custom init failed");
     goto fail;
   }