qed* : use trust mode to allow VF to override forced MAC

As per existing behavior, when PF sets a MAC address for a VF
(also called as forced MAC), VF is not allowed to change its
MAC address afterwards.
This puts the limitation on few use cases such as bonding of VFs,
where bonding driver asks VF to change its MAC address.

This patch uses a VF trust mode to allow VF to change its MAC address
in spite PF has set a forced MAC for that VF.

Signed-off-by: Shahed Shaikh <shahed.shaikh@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>