IPVS: netns preparation for proto_tcp

In this phase (one), all local vars will be moved to ipvs struct.

Remaining work, add param struct net *net to a couple of
functions that is common for all protos and use all
ip_vs_proto_data

*v3
Removed unused function as sugested by Simon

Signed-off-by: Hans Schillstrom <hans.schillstrom@ericsson.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>