UPSTREAM: zram: Delete gendisk before cleaning up the request queue

Remove the disk, partition and bdi sysfs attributes before cleaning up
the request queue associated with the disk.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

(cherry picked from commit 392db38058eb47250a9d0cc737af37e78a7e443d)
Signed-off-by: Peter Kalauskas <peskal@google.com>
Bug: 112488418
Change-Id: I89931dc1f7f52c1940d6b7f8f375e85eab59c75e