[media] rc: make s_tx_carrier consistent

LIRC_SET_SEND_CARRIER should return 0 on success or -errno.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/rc/mceusb.c

@@ -942,7 +942,7 @@ static int mceusb_set_tx_carrier(struct rc_dev *dev, u32 carrier)
 
 	}
 
-	return carrier;
+	return 0;
 }
 
 /*