i40e: Unset promiscuous settings on VF reset

This patch cleans up promiscuous configuration when a VF reset occurs.
Previously the promiscuous mode settings were still there after the VF
driver removal.

Signed-off-by: Mariusz Stachura <mariusz.stachura@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>