ixgbe: Add FCoE Storage MAC Address support

This patch implements the Storage Address entrypoint from the net device.
It will read the SAN MAC addresses from the EEPROM of the 82599 hardware,
and make them available to the FCoE stack through the net device.

Also, add/del the SAN MAC address to the netdev dev_addr_list via the
kernel api dev_addr_add()/dev_addr_del() when there is a valid SAN MAC
supported by the HW.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>