net/mlx5e: API to manipulate TTC rules destinations

Store the default destinations of the on-load generated TTC
(Traffic Type Classifier) rules in the ttc rules table.

Introduce TTC API functions to manipulate/restore and get the TTC rule
destination and use these API functions in arfs implementation.

This will allow a better decoupling between TTC implementation and its
users.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Maxim Mikityanskiy <maximmi@mellanox.com>