block: remove an outdated comment on the bd_dev field

kdev_t is long gone, so we don't need to comment a field isn't one..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2020-08-31 20:02:35 +02:00 • committed by Jens Axboe
commit 46d40cfad1