bnx2x: Fix failure to configure VF multicast filters

Commit 2dc33bbc "bnx2x: Remove the sriov VFOP mechanism" caused a regression,
preventing VFs from configuring multicast filters.

Signed-off-by: Naredner Kumar <narender.kumar@qlogic.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>