net/mlx5e: Reject unsupported CB Shaper TSA in ETS validation

net/mlx5e: Reject unsupported CB Shaper TSA in ETS validation

Credit Based (CB) TSA is not supported by the mlx5 driver, so reject
any configurations that specify it.

Fixes: 08fb1dacdd76 ("net/mlx5e: Support DCBNL IEEE ETS")
Signed-off-by: Alexei Lazar <alazar@nvidia.com>
Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://patch.msgid.link/20260717075125.1244877-3-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>