Currently, the sysctl net.netfilter.nf_hooks_lwtunnel depends on the
nf_conntrack module, but the nf_conntrack module is not always loaded.
Therefore, accessing net.netfilter.nf_hooks_lwtunnel may have an error.
Move sysctl nf_hooks_lwtunnel into the netfilter core.
Fixes: 7a3f5b0de3 ("netfilter: add netfilter hooks to SRv6 data plane")
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
a2225e0250