扫描线程未结束时关闭扫描仪，等待扫描线程结束

hgdriver/hgdev/hg_scanner.cpp

@@ -2462,6 +2462,8 @@ int hg_scanner::close(bool force)
 		{
 			LOG_INFO(LOG_LEVEL_WARNING, "close scanner: USB thread or Image thread is still running.\n");
 			io_->close();
+			while (scan_life_)
+				std::this_thread::sleep_for(std::chrono::milliseconds(5));
 			io_->release();
 			io_ = NULL;
 		}