PCI: pciehp: Handle push button event asynchronously

Use non-ordered workqueue for attention button events.

Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in pciehp as a result.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 085dbb5..27f4429 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -344,7 +344,7 @@
 		kfree(info);
 		goto out;
 	}
-	queue_work(pciehp_ordered_wq, &info->work);
+	queue_work(pciehp_wq, &info->work);
  out:
 	mutex_unlock(&p_slot->lock);
 }
@@ -439,7 +439,7 @@
 	else
 		p_slot->state = POWERON_STATE;
 
-	queue_work(pciehp_ordered_wq, &info->work);
+	queue_work(pciehp_wq, &info->work);
 }
 
 static void interrupt_event_handler(struct work_struct *work)