nodejs: user worker thread friendly initialization

Author: lukasz-jagielski-bolt

include/nodejs/node_osrm.hpp

@@ -39,6 +39,9 @@ struct Engine final : public Nan::ObjectWrap
 
 } // namespace node_osrm
 
-NODE_MODULE(osrm, node_osrm::Engine::Init)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+NAN_MODULE_WORKER_ENABLED(osrm, node_osrm::Engine::Init)
+#pragma GCC diagnostic pop
 
 #endif