ovs-tc: offload datapath rules matching on internal ports

ovs-tc: offload datapath rules matching on internal ports

Rules applied to OvS internal ports are not represented in TC datapaths.
However, it is possible to support rules matching on internal ports in TC.
The start_xmit ndo of OvS internal ports directs packets back into the OvS
kernel datapath where they are rematched with the ingress port now being
that of the internal port. Due to this, rules matching on an internal port
can be added as TC filters to an egress qdisc for these ports.

Allow rules applied to internal ports to be offloaded to TC as egress
filters. Rules redirecting to an internal port are also offloaded. These
are supported by the redirect ingress functionality applied in an earlier
patch.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>