netdev-dpdk: implement flow offload with rte flow

The basic yet the major part of this patch is to translate the "match"
to rte flow patterns. And then, we create a rte flow with MARK + RSS
actions. Afterwards, all packets match the flow will have the mark id in
the mbuf.

The reason RSS is needed is, for most NICs, a MARK only action is not
allowed. It has to be used together with some other actions, such as
QUEUE, RSS, etc. However, QUEUE action can specify one queue only, which
may break the rss. Likely, RSS action is currently the best we could
now. Thus, RSS action is choosen.

For any unsupported flows, such as MPLS, -1 is returned, meaning the
flow offload is failed and then skipped.

Co-authored-by: Yuanhan Liu <yliu@fridaylinux.org>
Signed-off-by: Finn Christensen <fc@napatech.com>
Signed-off-by: Yuanhan Liu <yliu@fridaylinux.org>
Co-authored-by: Shahaf Shuler <shahafs@mellanox.com>
Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
Signed-off-by: Ian Stokes <ian.stokes@intel.com>