elevator: remove an outdated comment in elevator_change

mq is no longer a special case.
Signed-off-by: Jinlong Chen <nickyc975@zju.edu.cn>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/cbf47824fc726440371e74c867bf635ae1b671a3.1669126766.git.nickyc975@zju.edu.cnSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/elevator.c

@@ -721,9 +721,6 @@ static int elevator_change(struct request_queue *q, const char *elevator_name)
 	if (!blk_queue_registered(q))
 		return -ENOENT;
 
-	/*
-	 * Special case for mq, turn off scheduling
-	 */
 	if (!strncmp(elevator_name, "none", 4)) {
 		if (q->elevator)
 			elevator_disable(q);