scsi: isci: Use the proper SCSI midlayer interfaces for PI

Use scsi_prot_ref_tag() instead of scsi_get_lba() to get the reference tag
for a given I/O.

Link: https://lore.kernel.org/r/20210806040023.5355-3-martin.petersen@oracle.comReviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/isci/request.c

@@ -341,7 +341,7 @@ static void scu_ssp_ireq_dif_insert(struct isci_request *ireq, u8 type, u8 op)
 	tc->reserved_E8_0 = 0;
 
 	if ((type & SCSI_PROT_DIF_TYPE1) || (type & SCSI_PROT_DIF_TYPE2))
-		tc->ref_tag_seed_gen = scsi_get_lba(scmd) & 0xffffffff;
+		tc->ref_tag_seed_gen = scsi_prot_ref_tag(scmd);
 	else if (type & SCSI_PROT_DIF_TYPE3)
 		tc->ref_tag_seed_gen = 0;
 }
@@ -369,7 +369,7 @@ static void scu_ssp_ireq_dif_strip(struct isci_request *ireq, u8 type, u8 op)
 	tc->app_tag_gen = 0;
 
 	if ((type & SCSI_PROT_DIF_TYPE1) || (type & SCSI_PROT_DIF_TYPE2))
-		tc->ref_tag_seed_verify = scsi_get_lba(scmd) & 0xffffffff;
+		tc->ref_tag_seed_verify = scsi_prot_ref_tag(scmd);
 	else if (type & SCSI_PROT_DIF_TYPE3)
 		tc->ref_tag_seed_verify = 0;