Update nodedev scsi_host data before use

* It appears that the udev event for HBA creation arrives before the
  associated sysfs data is fully populated, resulting in bogus data
  for the nodedev entry until the entry is refreshed.  This problem is
  particularly troublesome when creating NPIV vHBAs because it results
  in libvirt failing to find the newly created adapter and waiting for
  the full timeout period before erroneously failing the create
  operation.  This patch forces an update before any attempt to use
  any scsi_host nodedev entry.

src/node_device/node_device_driver.c

@@ -45,23 +45,9 @@ static int update_caps(virNodeDeviceObjPtr dev)
     virNodeDevCapsDefPtr cap = dev->def->caps;
 
     while (cap) {
-        /* The only cap that currently needs updating is the WWN of FC HBAs. */
+        /* The only caps that currently need updating are FC related. */
         if (cap->type == VIR_NODE_DEV_CAP_SCSI_HOST) {
-            if (cap->data.scsi_host.flags & VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST) {
-                if (read_wwn(cap->data.scsi_host.host,
-                            "port_name",
-                            &cap->data.scsi_host.wwpn) == -1) {
-                    VIR_ERROR(_("Failed to refresh WWPN for host%d"),
-                              cap->data.scsi_host.host);
-                }
-
-                if (read_wwn(cap->data.scsi_host.host,
-                            "node_name",
-                            &cap->data.scsi_host.wwnn) == -1) {
-                    VIR_ERROR(_("Failed to refresh WWNN for host%d"),
-                              cap->data.scsi_host.host);
-                }
-            }
+            check_fc_host(&dev->def->caps->data);
         }
         cap = cap->next;
     }
@@ -239,6 +225,7 @@ nodeDeviceLookupByWWN(virConnectPtr conn,
         while (cap) {
 
             if (cap->type == VIR_NODE_DEV_CAP_SCSI_HOST) {
+                check_fc_host(&cap->data);
                 if (cap->data.scsi_host.flags &
                     VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST) {