ice: add new VSI type for subfunctions

Add required plumbing for new VSI type dedicated to devlink subfunctions.
Make sure that the vsi is properly configured and destroyed. Also allow
loading XDP and AF_XDP sockets.

The first implementation of devlink subfunctions supports only one Tx/Rx
queue pair per given subfunction.

Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>