message: Add linux socket error code.
diff: @@ -34,7 +34,7 @@ $pm->parentFunc = function ($pid) use ($pm)
  assert(is_string($retData) and strlen($retData) > 0);
  $retData = $cli->recv();
  assert($retData == false);
  - assert($cli->errCode == SWOOLE_ERROR_CLIENT_NO_CONNECTION);
  + assert($cli->errCode === SWOOLE_ERROR_CLIENT_NO_CONNECTION || $cli->errCode === SOCKET_ECONNRESET);
  });
  swoole_event_wait();
  $pm->kill();
  @@ -68,4 +68,4 @@ $pm->childFunc = function () use ($pm) {
  $pm->childFirst();
  $pm->run();
  ?>
  ---EXPECTF--
  +--EXPECT--
  