qed: validate and restrict untrusted VFs vlan promisc mode

Today when VFs are put in promiscuous mode, they can request PF
to configure device for them to receive all VLANs traffic regardless
of what vlan is configured by the PF (via ip link) and PF allows this
config request regardless of whether VF is trusted or not.

From security POV, when VLAN is configured for VF through PF (via ip link),
honour such config requests from VF only when they are configured to be
trusted, otherwise restrict such VFs vlan promisc mode config.

Cc: stable@vger.kernel.org
Fixes: f990c82c ("qed*: Add support for ndo_set_vf_trust")
Signed-off-by: Manish Chopra <manishc@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>