net/mlx5: fs, add HWS root namespace functions

Add flow steering commands structure for HW steering. Implement create,
destroy and set peer HW steering root namespace functions.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20250109160546.1733647-2-tariqt@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>