Add programmer's guide doc to explain the design and use of the
GSO library.
Signed-off-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Acked-by: John McNamara <john.mcnamara@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
