ixgbe: save and restore pcie/msi state to support EEH recovery

To enable EEH support for pci-express network adapters, pcie/msi state
needs to be saved and restored for that adapter.

Tested this EEH patch with Intel 10G pci-express ixgbe adapter.

Signed-off-by: Wendy Xiong <wendyx@us.ibm.com>
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/ixgbe/ixgbe_main.c

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index cb371a8..7b85922 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -3431,6 +3431,7 @@
 	}
 
 	pci_set_master(pdev);
+	pci_save_state(pdev);
 
 #ifdef CONFIG_NETDEVICES_MULTIQUEUE
 	netdev = alloc_etherdev_mq(sizeof(struct ixgbe_adapter), MAX_TX_QUEUES);
@@ -3721,6 +3722,7 @@
 		return PCI_ERS_RESULT_DISCONNECT;
 	}
 	pci_set_master(pdev);
+	pci_restore_state(pdev);
 
 	pci_enable_wake(pdev, PCI_D3hot, 0);
 	pci_enable_wake(pdev, PCI_D3cold, 0);