OP-1122 OP-1125 fixed object connection leak in TelemetryMonitor

At each board connection a new connection would be added to the firmwareIAPObj
This would also cause some code to be later signaled mutliple times on board connection

ground/openpilotgcs/src/plugins/uavtalk/telemetrymonitor.cpp

@@ -179,6 +179,7 @@ void TelemetryMonitor::firmwareIAPUpdated(UAVObject *obj)
     QMutexLocker locker(mutex);
 
     if (firmwareIAPObj->getBoardType() != 0) {
+        disconnect(firmwareIAPObj);
         emit connected();
     }
 }