hpsa: correct initialization order issue

The driver was calling scsi_scan_host before enabling interrupts.

This has gone unnoticed except for customers running in intx mode.
Calling scsi_scan_host before interrupts are enabled causes
"irq XX: nobody cared" messages and the driver to hang.

This patch enables interrupts before the call to scsi_scan_host.

Reported-by: Piotr Karbowski <piotr.karbowski@gmail.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Reviewed-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 25aa219..9baf04e 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -8541,11 +8541,6 @@
 	if (rc)
 		goto clean6; /* sg, cmd, irq, shost, pci, lu, aer/h */
 
-	/* hook into SCSI subsystem */
-	rc = hpsa_scsi_add_host(h);
-	if (rc)
-		goto clean7; /* perf, sg, cmd, irq, shost, pci, lu, aer/h */
-
 	/* create the resubmit workqueue */
 	h->rescan_ctlr_wq = hpsa_create_controller_wq(h, "rescan");
 	if (!h->rescan_ctlr_wq) {
@@ -8642,6 +8637,11 @@
 		dev_info(&h->pdev->dev,
 			"Can't track change to report lun data\n");
 
+	/* hook into SCSI subsystem */
+	rc = hpsa_scsi_add_host(h);
+	if (rc)
+		goto clean7; /* perf, sg, cmd, irq, shost, pci, lu, aer/h */
+
 	/* Monitor the controller for firmware lockups */
 	h->heartbeat_sample_interval = HEARTBEAT_SAMPLE_INTERVAL;
 	INIT_DELAYED_WORK(&h->monitor_ctlr_work, hpsa_monitor_ctlr_worker);