net: stmmac: propagate feature flags to vlan

stmmac_dev_probe doesn't propagate feature flags to VLANs.  So features
like offloading don't correspond with the general features and it's not
possible to manipulate features via ethtool -K to affect VLANs.

Propagate feature flags to vlan features.  Drop TSO feature because
it does not work on VLANs yet.

Signed-off-by: Corinna Vinschen <vinschen@redhat.com>
Link: https://lore.kernel.org/r/20230417192845.590034-1-vinschen@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>