igb: call pci_save_state after pci_restore_state

This patch adds calls to pci_save_state() immediately after
calls to pci_restore_state(). Due to a change in the behavior
of pci_restore_state() it is necessary to call pci_save_state()
to keep the state_saved flag. This patch is based on a similar
patch for ixgbe.

Signed-off-by: Nicholas Nunley <nicholasx.d.nunley@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>