When vlan device is configured on top of the brige, it does
not support any offload capabilities because the bridge
device does not initiliaze vlan_fatures.  Set vlan_fatures to
be equivalent to hw_fatures.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>