block: add debugfs stanza for QUEUE_FLAG_NOWAIT

block: add debugfs stanza for QUEUE_FLAG_NOWAIT

[ Upstream commit dc30432605bbbd486dfede3852ea4d42c40a84b4 ]

This was missed in 021a24460dc2. Leads to the numeric value of
QUEUE_FLAG_NOWAIT (i.e. 29) showing up in
/sys/kernel/debug/block/*/state.

Fixes: 021a24460dc28e7412aecfae89f60e1847e685c0
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>