netfilter: nfnetlink_queue: rename related to nfqueue attaching conntrack info

The idea of this series of patch is to attach conntrack information to
nflog like nfqueue has already done. nfqueue conntrack info attaching
basis is generic, rename those names to generic one, glue.

Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>