Add "fixed" part of the user space Netlink Spec-based library.
This will get linked with the protocol implementations to form
a full API.
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We have a bit of documentation about the internals of Netlink
and the specs, but really the goal is for most people to not
worry about those. Add a practical guide for beginners who
want to poke at the specs.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>