[media] tm6000-dvb: Fix module unload

dvb_unregister_frontend has to be called before detach. Otherwise the
unregister call will segfault. This made tm6000-dvb module unload unusable.
Signed-off-by: NJulian Scheel <julian@jusst.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/tm6000/tm6000-dvb.c

@@ -360,8 +360,8 @@ static int register_dvb(struct tm6000_core *dev)
 	dvb_dmx_release(&dvb->demux);
 frontend_err:
 	if (dvb->frontend) {
-		dvb_frontend_detach(dvb->frontend);
 		dvb_unregister_frontend(dvb->frontend);
+		dvb_frontend_detach(dvb->frontend);
 	}
 adapter_err:
 	dvb_unregister_adapter(&dvb->adapter);
@@ -384,8 +384,8 @@ static void unregister_dvb(struct tm6000_core *dev)
 
 /*	mutex_lock(&tm6000_driver.open_close_mutex); */
 	if (dvb->frontend) {
-		dvb_frontend_detach(dvb->frontend);
 		dvb_unregister_frontend(dvb->frontend);
+		dvb_frontend_detach(dvb->frontend);
 	}
 
 	dvb_dmxdev_release(&dvb->dmxdev);