Add support for SRIOV: send the requested number of VFs
to the device Control Plane, via the virtchnl message
and then enable the VFs using 'pci_enable_sriov'.

Add other ndo ops supported by the driver such as features_check,
set_rx_mode, validate_addr, set_mac_address, change_mtu, get_stats64,
set_features, and tx_timeout. Initialize the statistics task which
requests the queue related statistics to the CP. Add loopback
and promiscuous mode support and the respective virtchnl messages.

Finally, add documentation and build support for the driver.
Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
Co-developed-by: Alan Brady <alan.brady@intel.com>
Signed-off-by: Alan Brady <alan.brady@intel.com>
Co-developed-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Madhu Chittim <madhu.chittim@intel.com>
Co-developed-by: Phani Burra <phani.r.burra@intel.com>
Signed-off-by: Phani Burra <phani.r.burra@intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Co-developed-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
Signed-off-by: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>