net/mlx5: Lag, set LAG traffic type mapping

Generate a traffic type bitmap that will define which
steering objects we need to create for the steering
based LAG.

Bits in this bitmap are set according to the LAG hash type.
In addition, have a field that indicate if the lag is in encap
mode or not.

Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>