http2:settings fix warning

Author: martenrichter

src/node_http2.cc

@@ -314,8 +314,8 @@ void Http2Settings::Update(Http2Session* session, get_setting fn, bool local) {
   for (size_t i = 0; i < imax; i++) {
     // We flag unset the settings with a bit above the allowed range
     if (!(custom_settings.entries[i].settings_id & (~0xffff))) {
-      int32_t settings_id =
-          (int32_t)(custom_settings.entries[i].settings_id & 0xffff);
+      uint32_t settings_id =
+          (uint32_t)(custom_settings.entries[i].settings_id & 0xffff);
       size_t j = 0;
       while (j < count) {
         if ((buffer[IDX_SETTINGS_COUNT + 1 + j * 2 + 1] & 0xffff) ==