reason it's dropped before passing to bridge: when a vlan interface is
in promisc mode, it will loop the packet back to ether_input() with
M_PROMISC set, and when carp calls ether_input again the flag is still
there and the packet is dropped. If the carp interface doesn't take
the packet M_PROMISC is set just after is needed anyway.
Tested on a box with multiple carp on vlans, no comments about this patch
on tech-net@
53bfe8e81c