net/mlx5: Add no-op implementation for setting tc-bw on rate objects

Introduce `mlx5_esw_devlink_rate_node_tc_bw_set()` and
`mlx5_esw_devlink_rate_leaf_tc_bw_set()` with no-op logic.

Future patches will add support for setting traffic class bandwidth
on rate objects.

Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250629142138.361537-5-mbloch@nvidia.com


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