ixgbe: report link state for VF devices

The link state of VF devices can be controlled via "ip link set", but the
current state (auto/disabled) is not reported by "ip link show".

Update ixgbe_ndo_get_vf_config() to make this info available to userspace.

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>