loop: Simplify discard granularity calc

A bdev discard granularity is always at least SECTOR_SIZE, so don't check
for a zero value.

Suggested-by: Christoph Hellwig <[email protected]>
Signed-off-by: John Garry <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

Author: johnpgarry

drivers/block/loop.c

@@ -789,8 +789,7 @@ static void loop_config_discard(struct loop_device *lo,
 		struct block_device *bdev = I_BDEV(inode);
 
 		max_discard_sectors = bdev_write_zeroes_sectors(bdev);
-		granularity = bdev_discard_granularity(bdev) ?:
-			bdev_physical_block_size(bdev);
+		granularity = bdev_discard_granularity(bdev);
 
 	/*
 	 * We use punch hole to reclaim the free space used by the