block: fix memory leak for elevator on add_disk failure

mainline inclusion
from mainline-v6.1-rc3
commit 02341a08
category: bugfix
bugzilla: 188733

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=02341a08c9dec5a88527981b0bdf0fb6f7499cbf



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The default elevator is allocated in the beginning of device_add_disk(),
however, it's not freed in the following error path.

Fixes: 50e34d78 ("block: disable the elevator int del_gendisk")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20221022021615.2756171-1-yukuai1@huaweicloud.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>
confilic:
  block/genhd.c
Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>
Signed-off-by: Li Nan <linan122@huawei.com>