- ingress hook:
    - if port is a tunnel port, use tunnel info in
      attached dst_metadata to map it to a local vlan
- egress hook:
    - if port is a tunnel port, use tunnel info attached to
      vlan to set dst_metadata on the skb

CC: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>