s390/dcssblk:: don't call bio_split_to_limits

s390 iterates over the bio using bio_for_each_segment and doesn't need
any bio splitting.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/r/20230123075356.60847-1-hch@lst.de


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