igb: Use device_set_wakeup_enable

Since dev->power.should_wakeup bit is used by the PCI core to
decide whether the device should wake up the system from sleep
states, set/unset this bit whenever WOL is enabled/disabled using
igb_set_wol().  Accordingly, use device_can_wakeup() for checking
if wake-up is supported by the device.

Signed-off-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index 1f397cd..0a98015 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -1244,6 +1244,7 @@
 
 	/* initialize the wol settings based on the eeprom settings */
 	adapter->wol = adapter->eeprom_wol;
+	device_set_wakeup_enable(&adapter->pdev->dev, adapter->wol);
 
 	/* reset the hardware with the new settings */
 	igb_reset(adapter);