enic: Use VF mac set by IFLA_VF_MAC in port profile provisioning data

This patch adds support in enic 802.1Qbh port profile provisioning code
to use the mac address set by IFLA_VF_MAC. For now we handle this mac as a
special case for a VM mac address sent to us by libvirt. The VM mac address
is sent to the switch along with the rest of the port profile provisioning
data. This patch also adds calls to register and deregister the mac address
during port profile association/deassociation.

Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
Signed-off-by: David Wang <dwang2@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>