be2net: don't delete MAC on close on unprivileged BE3 VFs

BE3 VFs without FILTMGMT privilege are not allowed to modify its MAC,
VLAN table and UC/MC lists. So don't try to delete MAC on such VFs.

Cc: Sathya Perla <sathya.perla@broadcom.com>
Cc: Ajit Khaparde <ajit.khaparde@broadcom.com>
Cc: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Cc: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Ivan Vecera <cera@cera.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>