vlan filtering

[Jack Vogel]

I was just working on a bug in the Oplin driver that had me look
a bit more at VLAN code than I had previously.

FreeBSD has apparently never used the hardware vlan filtering
that our hardware can do, is there a systemic reason for this,
or has the code lagged in its use of the system?

I at least don't understand how the driver is supposed to get
the vlan id to set in the filter, am I just unenlightened? :)

If this is doable I can add code into em as well as ixgbe.

Jack