IPVS: netns, add basic init per netns.

Preparation for network name-space init, in this stage
some empty functions exists.

In most files there is a check if it is root ns i.e. init_net
if (!net_eq(net, &init_net))
        return ...
this will be removed by the last patch, when enabling name-space.

*v3
 ip_vs_conn.c merge error corrected.
 net_ipvs #ifdef removed as sugested by Jan Engelhardt

[ horms@verge.net.au: Removed whitespace-change-only hunks ]
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>