fix node recursive lock.

lichao

2021-05-06 2de7ebf4516e58a8fa959977a51dccd22823c0e0

 src/topic_node.cpp

@@ -77,8 +77,6 @@

void TopicNode::Start(ServerAsyncCB const &server_cb, SubDataCB const &sub_cb, RequestResultCB &client_cb, int nworker)
{
   std::lock_guard<std::mutex> lk(mutex_);

   if (!Init()) {
      SetLastError(eError, "BHome Node Not Inited.");
      return;