[SCSI] sd: Return correct error code for DIF

sd_dif.c was not updated to return -EILSEQ, leading to error handling
failures in applications which provide their own integrity metadata (as
opposed to being protected by the block layer functions).
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

drivers/scsi/sd_dif.c

@@ -418,7 +418,7 @@ int sd_dif_prepare(struct request *rq, sector_t hw_sector, unsigned int sector_s
 		  __func__, virt, phys, be32_to_cpu(sdt->ref_tag),
 		  be16_to_cpu(sdt->app_tag));
 
-	return -EIO;
+	return -EILSEQ;
 }
 
 /*