scsi: lpfc: Restore clearing of NLP_UNREG_INP in ndlp->nlp_flag

scsi: lpfc: Restore clearing of NLP_UNREG_INP in ndlp->nlp_flag

Commit 32566a6f1ae5 ("scsi: lpfc: Remove NLP_RELEASE_RPI flag from nodelist
structure") introduced a regression with SLI-3 adapters (e.g. LPe12000 8Gb)
where a Link Down / Link Up such as caused by disabling an host FC switch
port would result in the devices remaining in the transport-offline state
and multipath reporting them as failed.  This problem was not seen with
newer SLI-4 adapters.

The problem was caused by portions of the patch which removed the functions
__lpfc_sli_rpi_release() and lpfc_sli_rpi_release() and all their callers.
This was presumably because with the removal of the NLP_RELEASE_RPI flag
there was no need to free the rpi.

However, __lpfc_sli_rpi_release() and lpfc_sli_rpi_release() which calls it
reset the NLP_UNREG_INP flag. And, lpfc_sli_def_mbox_cmpl() has a path
where __lpfc_sli_rpi_release() was called in a particular case where
NLP_UNREG_INP was not otherwise cleared because of other conditions.

Restoring the else clause of this conditional and simply clearing the
NLP_UNREG_INP flag appears to resolve the problem with SLI-3 adapters.  It
should be noted that the code path in question is not specific to SLI-3,
but there are other SLI-4 code paths which may have masked the issue.

Fixes: 32566a6f1ae5 ("scsi: lpfc: Remove NLP_RELEASE_RPI flag from nodelist structure")
Cc: stable@vger.kernel.org
Tested-by: Marco Patalano <mpatalan@redhat.com>
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Link: https://lore.kernel.org/r/20250317163731.356873-1-emilne@redhat.com
Reviewed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>