ixgbe: Enable ACPI WoL capabilities for 82599

The 82599 KX4 device defaults to legacy power management, or APME.  This
puts the device into ACPI mode, which allows more robust WoL setups to
work properly.
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ixgbe/ixgbe_main.c

@@ -5282,6 +5282,9 @@ static int __devinit ixgbe_probe(struct pci_dev *pdev,
 	case IXGBE_DEV_ID_82599_KX4:
 		adapter->wol = (IXGBE_WUFC_MAG | IXGBE_WUFC_EX |
 		                IXGBE_WUFC_MC | IXGBE_WUFC_BC);
+		/* Enable ACPI wakeup in GRC */
+		IXGBE_WRITE_REG(hw, IXGBE_GRC,
+		             (IXGBE_READ_REG(hw, IXGBE_GRC) & ~IXGBE_GRC_APME));
 		break;
 	default:
 		adapter->wol = 0;