scsi: lpfc: do not set queue->page_count to 0 if pc_sli4_params.wqpcnt is invalid

Certain older adapters such as the OneConnect OCe10100 may not have a valid
wqpcnt value.  In this case, do not set queue->page_count to 0 in
lpfc_sli4_queue_alloc() as this will prevent the driver from initializing.

Fixes: 895427bd ("scsi: lpfc: NVME Initiator: Base modifications")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>