fix re-register fail.

lichao

2021-05-18 b4a8d1632c2b4a3d4dc6e03d732fa3e93fd0731e

 src/shm.cpp

@@ -25,6 +25,7 @@
    mshm_t(open_or_create, name.c_str(), size, 0, AllowAll()),
    name_(name)
{
   pmutex_ = FindOrCreate<Mutex>("ShmSelfControlMutex0");
}

SharedMemory::~SharedMemory()