net/mlx5e: Infrastructure for duplicated offloading of TC flows

Under uplink LAG or multipath schemes, traffic that matches one flow
might arrive on both uplink ports and transmitted through both
as part of supporting aggregation and high-availability.

To cope with the fact that the SW model might use logical SW port
(e.g uplink team or bond) but we have two HW ports with e-switch on
each, there are cases where in order to offload a SW TC rule we
need to duplicate it to two HW flows.

Since each HW rule has its own counter we also aggregate the counter
of both rules when a flow stats query is executed from user-space.

Introduce the changes for the different elements (add/delete/stats),
currently nothing is duplicated.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Aviv Heller <avivh@mellanox.com>
Signed-off-by: Shahar Klein <shahark@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>