netfilter: move tee_active to core

netfilter: move tee_active to core

This prepares for a TEE like expression in nftables.
We want to ensure only one duplicate is sent, so both will
use the same percpu variable to detect duplication.

The other use case is detection of recursive call to xtables, but since
we don't want dependency from nft to xtables core its put into core.c
instead of the x_tables core.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
(cherry picked from commit e7c8899f3e6f2830136cf6e115c4a55ce7a3920a)

Orabug: 24694570

Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
Reviewed-by: Dhaval Giani <dhaval.giani@oracle.com>