lagg0.2 style vlans on lagg(4) interface

[Niki Denev]

If one tries to use lagg0.2 style vlans on lagg0 interface configured
from rc.conf it does't work.
The problem is that all of the cloned interfaces (lagg0 , lagg0.2, etc)
are created before any other interface configuration is done,
and in this case lagg0 is created, then lagg0.2 is created.
But because lagg0 does not have any members yet, it's MAC address
is all zeroes, and this is inherited by the vlan interfaces.
At the next step the members are added to the lagg0 interface and it's
mac address gets set,
but the vlan interfaces never see this change and remain with mac
address 00:00:00:00:00:00 and in unusable state.

Does it sound reasonable for the vlan(4) interfaces to update their
mac address when their parent changes it.
(this should probably look more like the parent telling the vlans
attached to it that it's mac has changed, but
i'm not sure if the parent knows about children interfaces)