bnxt_en: Add support for ndo_set_vf_trust

Trusted VFs are allowed to modify MAC address, even when PF
has assigned one.

Signed-off-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>