ixgbe: clean macvlan MAC filter table on VF reset

Flush the macvlan filters on VF reset to avoid conflict with other VFs that
may end up using the same MAC address.

The main change here is the call to ixgbe_set_vf_macvlan() with index 0.

Moved ixgbe_set_vf_macvlan() in front of ixgbe_vf_reset_event() to avoid
adding a prototype.

Reported-by: Sritej Kanakadandi Sritej Rama <skanakad@cisco.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>