Use new signal switchChanged for monitoring closing the lid

This resolves Bug 2052

src/hardware.cpp

@@ -603,6 +603,7 @@ bool HardwareInfo::intialiseHWInfo() {
 			if (!allUDIs.contains( hwdevice->uniqueID() )) {
 				allUDIs.append( hwdevice->uniqueID() );
 			}
+			connect(edevice, TQT_SIGNAL(switchChanged()), this, TQT_SLOT(checkLidcloseState()));
 			checkLidcloseState();
 		}
 	}