igb: Add Anti-spoofing feature support

Add support for the anti-spoofing feature in the HW.  Packets from
VF devices with spoofed MAC addresses or VLAN tags will be blocked
and an event generated.  When the watchdog task runs it will call a
function to check if any spoof events occurred.  If an event was
detected then a warning message is dumped to the system log.

Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>