nfp: add SR-IOV trusted VF support

By default VFs are not trusted. Add ndo_set_vf_trust support to toggle
a new per-VF bit. Coupled with FW with this capability allows a
trusted VF to change its MAC even after being administratively set by
the PF. Also populate the trusted field on ndo_get_vf_config. Add the
same ndo to the representors.

Signed-off-by: Pablo Cascón <pablo.cascon@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>