V4L/DVB: tm6000: fix: avoid unregister the driver after success

After successfully running tm6000_init_dev, due to a lack of a return(),
the driver runs the error code, unregistering the device.
Signed-off-by: Stefan Ringel <stefan.ringel@arcor.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/tm6000/tm6000-cards.c

@@ -421,6 +421,7 @@ static int tm6000_init_dev(struct tm6000_core *dev)
 		}
 #endif
 	}
+	return 0;
 
 err2:
 	v4l2_device_unregister(&dev->v4l2_dev);