update cni version to 0.7.5 to avoid CNI-HOSTPORT-DNAT problem

[ckcd]

The problem is: when using IPVS mode in kube-proxy, with a hostPort (assume 80) defines in a nodes, then all traffics from this node to any service:80 will be failed, actually wrongly be DNAT to this hostPort pod.

Relate discuss:
kubernetes/kubernetes#66103
containernetworking/plugins#222
kubernetes/kubernetes#62718

The reason is because the order of two chains in iptables: CNI-HOSTPORT-DNAT and KUBE-SERVICES :

Chain PREROUTING (policy ACCEPT 1 packets, 60 bytes)
 pkts bytes target     prot opt in     out     source               destination
 5953  548K CNI-HOSTPORT-DNAT  all  --  *      *       0.0.0.0/0            0.0.0.0/0            ADDRTYPE match dst-type LOCAL
 6894  606K KUBE-SERVICES  all  --  *      *       0.0.0.0/0            0.0.0.0/0            /* kubernetes service portals */

which is, the correct order is KUBE-SERVICES must be ahead of CNI-HOSTPORT-DNAT, we can find more details in here, and if the CNI-HOSTPORT-DNAT is at the first line, then there will be problem.

The solution: in cni-plugins-portmap, they makes some changes to make the CNI-HOSTPORT-DNAT always in last position, and this problem will be solved, relate commit is: Portmap: append

But, this changes only available in version 0.7.5 (and newer), so i think maybe we can update our cni version from 0.6.0 to 0.7.5.

Thanks a lot !!!