Add a Netlink spec in YAML for getting very basic information about page pools. Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>