block: Fix format string mismatch in cfq-iosched.c

Fix format string mismatch in cfq_var_show()
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

block/cfq-iosched.c

@@ -4460,7 +4460,7 @@ static int cfq_init_queue(struct request_queue *q, struct elevator_type *e)
 static ssize_t
 cfq_var_show(unsigned int var, char *page)
 {
-	return sprintf(page, "%d\n", var);
+	return sprintf(page, "%u\n", var);
 }
 
 static ssize_t