Modify netdev->features for vlan stripping based on virtual
channel messages received from the PF. Change is needed
to synchronize vlan strip status between PF sysfs and iavf ethtool.

Fixes: 5951a2b9 ("iavf: Fix VLAN feature flags after VFR")
Signed-off-by: NNorbert Ciosek <norbertx.ciosek@intel.com>
Signed-off-by: NMichal Maloszewski <michal.maloszewski@intel.com>
Tested-by: NKonrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>