scsi: lpfc: Fix deadlock on host_lock during cable pulls

During cable pull testing a deadlock was seen between lpfc_nlp_counters()
vs lpfc_mbox_process_link_up() vs lpfc_work_list_done(). They are all
waiting on the shost->host_lock.

Issue is all of these cases raise irq when taking out the lock but use
spin_unlock_irq() when unlocking. The unlock path is will unconditionally
re-enable interrupts in cases where irq state should be preserved. The
re-enablement allowed the other paths to execute which then causes the
deadlock.

Fix by converting the lock/unlock to irqsave/irqrestore.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>