scsi: qla2xxx: Initialize port speed to avoid setting lower speed

This patch initializes port speed so that firmware does not set lower
operating speed. Setting lower speed in firmware impacts WRITE perfomance.

Fixes: 726b8548 ("qla2xxx: Add framework for async fabric discovery")
Cc: <stable@vger.kernel.org>
Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>