block: only zero non-PI metadata tuples in bio_integrity_prep

The PI generation helpers already zero the app tag, so relax the zeroing
to non-PI metadata.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240626045950.189758-2-hch@lst.de


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