scsi: lpfc: Fix pt2pt discovery on SLI3 HBAs

After exchanging PLOGI on an SLI-3 adapter, the PRLI exchange failed.  Link
trace showed the port was assigned a non-zero n_port_id, but didn't use the
address on the PRLI. The assigned address is set on the port by the
CONFIG_LINK mailbox command. The driver responded to the PRLI before the
mailbox command completed. Thus the PRLI response used the old n_port_id.

Defer the PRLI response until CONFIG_LINK completes.

Link: https://lore.kernel.org/r/20190922035906.10977-2-jsmart2021@gmail.com
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>