scsi: lpfc: Remove reftag check in DIF paths

When preparing protection DIF I/O for DMA, the driver obtains reference
tags from scsi_prot_ref_tag().  Previously, there was a wrong assumption
that an all 0xffffffff value meant error and thus the driver failed the
I/O.  This patch removes the evaluation code and accepts whatever the upper
layer returns.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20230803211932.155745-1-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>