netfilter: ipvs: make global sysctl readonly in non-init netns
Because the data pointer of net/ipv4/vs/debug_level is not updated per netns, it must be marked as read-only in non-init netns. Fixes: c6d2d445 ("IPVS: netns, final patch enabling network name space.") Signed-off-by: Antoine Tenart <atenart@kernel.org> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>