net/mlx5: DR, Support SW created encap actions for FW table

In some cases, steering might need to use SW-created action in
FW table, which results in wrong packet reformat being used:

mlx5_core 0000:81:00.1: mlx5_cmd_check:756:(pid 1154):
SET_FLOW_TABLE_ENTRY(0×936) op_mod(0×0) failed,
status bad resource(0×5), syndrome (0xf2ff71)

This patch adds support for usage of SW-created packet reformat (encap)
actions in FW tables, and adds clear error flow for attempt to use
SW-created modify header on FW tables.

Fixes: 6a48faeeca10 ("net/mlx5: Add direct rule fs_cmd implementation")
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Erez Shitrit <erezsh@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Remove unused structs

Remove structs which are no longer used in the driver:
mlx5dr_cmd_qp_create_attr
mlx5_fs_dr_ns
mlx5_pas

Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Add direct rule fs_cmd implementation

Add support to create flow steering objects
via direct rule API (SW steering).
New layer is added - fs_dr, this layer translates the command that
fs_core sends to the FW into direct rule API. In case that direct
rule is not supported in some feature then -EOPNOTSUPP is
returned.

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