block/bdev: use helper for max block size check

We already have a helper for checking the limits on the block size
both low and high, just use that.

No functional changes.

Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241218020212.3657139-2-mcgrof@kernel.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>