catch时增加返回！

CcosThread/CcosThread.cpp

@@ -87,9 +87,11 @@ void* Thread_Base::Thread_Base_Thread(void* pPara) {
     }
     catch (const std::exception& e) {
         ERR_LOG("[Thread] Exception: " << e.what());
+        return nullptr;
     }
     catch (...) {
         ERR_LOG("[Thread] Unknown exception");
+        return nullptr;
     }
     return nullptr;
 }