netfilter: xt_CT: fix usersize for v1 and v2 revision

netfilter: xt_CT: fix usersize for v1 and v2 revision

While resurrecting the conntrack-tool test cases I found following bug:
In:
iptables -I OUTPUT -t raw -p 13 -j CT --timeout test-generic
Out:
[0:0] -A OUTPUT -p 13 -j CT --timeout test

Data after first four bytes of the timeout policy name is never
copied to userspace because its treated as kernel-only.

Fixes: ec2318904965 ("xtables: extend matches and targets with .usersize")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>