Automatic merge from submit-queue
[WIP] Skip resize of nf_conntrack/parameters/hashsize if not necessary
**What this PR does / why we need it**:
Linux does not support writing to `/sys/module/nf_conntrack/parameters/hashsize` when the writer process is not in the initial network namespace
(https://github.com/torvalds/linux/blob/v4.10/net/netfilter/nf_conntrack_core.c#L1795-L1796).
Usually that's fine. But in some configurations such as with https://github.com/kinvolk/kubeadm-nspawn, kube-proxy is in another netns.
Therefore, check if writing in hashsize is necessary and skip the writing if not.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
```
10704b2ae1