net/mlx5: support meter policy operations

net/mlx5: support meter policy operations

MLX5 PMD checks the validation of actions in policy while add
a new meter policy, if pass the validation, allocates the new
policy object from the meter policy indexed memory pool.

It is common to use the same policy for multiple meters.
MLX5 PMD supports two types of policy: termination policy and
no-termination policy.

Implement the next policy operations:
validate:
The driver doesn't support to configure actions in the flow
after the meter action except one case when the meter policy
is configured to do nothing in GREEN\YELLOW and only DROP action
in RED, this special policy is called non-terminated policy
and is handed as a singleton object internally.

For all the terminated policies, the next actions are supported:
GREEN - QUEUE, RSS, PORT_ID, JUMP, DROP, MARK and SET_TAG.
YELLOW - not supported at all -> must be empty.
RED - must include DROP action.

Hence, in ingress case, for example,
QUEUE\RSS\JUMP must be configured as last action for GREEN color.

All the above limitations will be validated.

create:
Validate the policy configuration.
Prepare the related tables and actions.

destroy:
Release the created policy resources.

Signed-off-by: Li Zhang <lizh@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>