ublk_drv: remove nr_aborted_queues from ublk_device

No one uses 'nr_aborted_queues' any more, so remove it.
Reviewed-by: ZiyangZhang <ZiyangZhang@linux.alibaba.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230106041711.914434-2-ming.lei@redhat.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/ublk_drv.c

@@ -159,7 +159,6 @@ struct ublk_device {
 
 	struct completion	completion;
 	unsigned int		nr_queues_ready;
-	atomic_t		nr_aborted_queues;
 
 	/*
 	 * Our ubq->daemon may be killed without any notification, so