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: NEwan D. Milne <emilne@redhat.com>
Reviewed-by: NLaurence Oberman <loberman@redhat.com>
Tested-by: NLaurence Oberman <loberman@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/lpfc/lpfc_sli.c

@@ -14575,7 +14575,8 @@ lpfc_sli4_queue_alloc(struct lpfc_hba *phba, uint32_t page_size,
 			hw_page_size))/hw_page_size;
 
 	/* If needed, Adjust page count to match the max the adapter supports */
-	if (queue->page_count > phba->sli4_hba.pc_sli4_params.wqpcnt)
+	if (phba->sli4_hba.pc_sli4_params.wqpcnt &&
+	    (queue->page_count > phba->sli4_hba.pc_sli4_params.wqpcnt))
 		queue->page_count = phba->sli4_hba.pc_sli4_params.wqpcnt;
 
 	INIT_LIST_HEAD(&queue->list);