block: don't reduce max_sectors based on io_opt

Don't reduce the max_sectors value below the normal cap when the driver
advertsizes a very low io_opt.  This restores the behavior we had before
the recent changes to the max_sectors calculation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20240701051800.1245240-3-hch@lst.de


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