[media] rc: unlock on error in store_protocols()

This error path is missing the unlock.

[mchehab@redhat.com: Merged two equal patches into one]
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/rc/rc-main.c

@@ -892,7 +892,8 @@ static ssize_t store_protocols(struct device *device,
 
 		if (i == ARRAY_SIZE(proto_names)) {
 			IR_dprintk(1, "Unknown protocol: '%s'\n", tmp);
-			return -EINVAL;
+			ret = -EINVAL;
+			goto out;
 		}
 
 		count++;