dasd: don't set the discard_alignment queue limit

The discard_alignment queue limit is named a bit misleading means the
offset into the block device at which the discard granularity starts.
Setting it to PAGE_SIZE while the discard granularity is the block size
that is smaller or the same as PAGE_SIZE as done by dasd is mostly
harmless but also useless.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220418045314.360785-8-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/s390/block/dasd_fba.c

@@ -782,7 +782,6 @@ static void dasd_fba_setup_blk_queue(struct dasd_block *block)
 	blk_queue_segment_boundary(q, PAGE_SIZE - 1);
 
 	q->limits.discard_granularity = logical_block_size;
-	q->limits.discard_alignment = PAGE_SIZE;
 
 	/* Calculate max_discard_sectors and make it PAGE aligned */
 	max_bytes = USHRT_MAX * logical_block_size;