block: return unsigned int from bdev_io_min

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

Fixes: ac481c2 ("block: Topology ioctls")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20241119072602.1059488-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

include/linux/blkdev.h

@@ -1261,7 +1261,7 @@ static inline unsigned int queue_io_min(const struct request_queue *q)
 	return q->limits.io_min;
 }
 
-static inline int bdev_io_min(struct block_device *bdev)
+static inline unsigned int bdev_io_min(struct block_device *bdev)
 {
 	return queue_io_min(bdev_get_queue(bdev));
 }