block: return unsigned int from bdev_io_opt

The underlying limit is defined as an unsigned int, so return that from
bdev_io_opt as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20241119160932.1327864-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

include/linux/blkdev.h

@@ -1275,7 +1275,7 @@ static inline unsigned int queue_io_opt(const struct request_queue *q)
 	return q->limits.io_opt;
 }
 
-static inline int bdev_io_opt(struct block_device *bdev)
+static inline unsigned int bdev_io_opt(struct block_device *bdev)
 {
 	return queue_io_opt(bdev_get_queue(bdev));
 }