fix Warning

qt6-after/qt6-migrated-legatus/TetraIF/PrtCnv/PrtCnvTelegramLogThread.cpp

@@ -162,7 +162,7 @@ void PrtCnvTelegramLogThread::writeTelegramLog(const QByteArray &a_data, int a_p
 
   
   QFile telegramFile(fileName);
-  telegramFile.open(QIODevice::WriteOnly | QIODevice::Append);
+  (void)telegramFile.open(QIODevice::WriteOnly | QIODevice::Append);
 
   
   N_CoPrtCnv::CoPrtCnvLogHeader lh;