block: move rq_qos_exit() into disk_release()

Keep all teardown of file system I/O related functionality in one place.
There can't be file system I/O in disk_release(), so it is safe to move
rq_qos_exit() there.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308055200.735835-15-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/genhd.c

@@ -627,7 +627,6 @@ void del_gendisk(struct gendisk *disk)
 
 	blk_mq_freeze_queue_wait(q);
 
-	rq_qos_exit(q);
 	blk_sync_queue(q);
 	blk_flush_integrity();
 	/*
@@ -1119,7 +1118,7 @@ static void disk_release_mq(struct request_queue *q)
 		elevator_exit(q);
 		mutex_unlock(&q->sysfs_lock);
 	}
-
+	rq_qos_exit(q);
 	__blk_mq_unfreeze_queue(q, true);
 }