scsi: lpfc: Prevent failure to reregister with NVMe transport after PRLI retry

A failure to unregister with the NVMe transport may occur when a PRLI is
retried.

Remove duplicate testing of NLP_NVME_TARGET flag. Add a secondary check
of the registered state based on the nrport information.  Further qualify
the ndlp reference count modification when nvme_fc_register_remoteport()
returns an error.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20250425194806.3585-5-justintee8345@gmail.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>