net/mlx5: HWS, added rules handling

Steering rule is a concept that includes match parameters for a flow,
and actions to perform on the flows that match these parameters.
This patch adds rules handling part of HW Steering.

Reviewed-by: Itamar Gozlan <[email protected]>
Signed-off-by: Yevgeny Kliteynik <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>

Author: kliteyn