Fix NO_GLOBAL_INSTANCES

libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp

@@ -849,6 +849,10 @@ bool HTTPClient::connect(void)
 {
  if(_reuse && _canReuse && connected()) {
  DEBUG_HTTPCLIENT("[HTTP-Client] connect: already connected, reusing connection\n");
+
+#if defined(NO_GLOBAL_INSTANCES)
+ StreamNull devnull;
+#endif
  _client->sendAvailable(devnull); // clear _client's output (all of it, no timeout)
  return true;
  }