dm-log-writes: set dma_alignment limit in io_hints

This device mapper needs bio vectors to be sized and memory aligned to
the logical block size. Set the minimum required queue limit
accordingly.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20221110184501.2451620-6-kbusch@meta.com


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