[media] RedRat3: Improve another size determination in redrat3_reset()

Replace the specification of a data type by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/rc/redrat3.c

@@ -536,7 +536,7 @@ static void redrat3_reset(struct redrat3_dev *rr3)
 	struct device *dev = rr3->dev;
 	int rc, rxpipe, txpipe;
 	u8 *val;
-	int len = sizeof(u8);
+	size_t const len = sizeof(*val);
 
 	rxpipe = usb_rcvctrlpipe(udev, 0);
 	txpipe = usb_sndctrlpipe(udev, 0);