eth: mlx5: expose NETIF_F_NTUPLE when ARFS is compiled out

ARFS depends on NTUPLE filters, but the inverse is not true.
Drivers which don't support ARFS commonly still support NTUPLE
filtering. mlx5 has a Kconfig option to disable ARFS (MLX5_EN_ARFS)
and does not advertise NTUPLE filters as a feature at all when ARFS
is compiled out. That's not correct, ntuple filters indeed still work
just fine (as long as MLX5_EN_RXNFC is enabled).

This is needed to make the RSS test not skip all RSS context
related testing.

Acked-by: Saeed Mahameed <saeedm@nvidia.com>
Link: https://patch.msgid.link/20240711223722.297676-1-kuba@kernel.org


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