net/mlx5e: Add tc chains offload support for nic flows

Allow adding nic tc flow rules with goto chain action.

Connecting the nic flows to the mlx5 chains infrastructure in previous
patches allows us to support the creation of chained flow tables and
rules that direct to another chain for further packet processing.
This is a required preparation to support CT offloads for nic tc flows.

We allow the creation of 256 different chains for nic flows since we
have 8 bits available for the chain restore tag in case of a miss.

Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>