scsi: elx: libefc: Fix IRQ restore in efc_domain_dispatch_frame()

Calling a nested spin_lock_irqsave() will overwrite the original "flags" so
that they can not be enabled again at the end.

Link: https://lore.kernel.org/r/YMyjH16k4M1yEmmU@mwanda


Fixes: 3146240f ("scsi: elx: libefc: FC Domain state machine interfaces")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>