Fix kube-router config generation

[MrFreezeex]

What type of PR is this?
/kind bug

What this PR does / why we need it:
The cni config and the kubeconfig were not updated on a new deployment of the playbook.
The apiserver ip in the kubeconfig was sometimes incorrect.

This PR solves those two issues by generating those two files with ansible instead of relying on a configmap and an initContainer deployed on the first master.
See the issue for more details about it.

Which issue(s) this PR fixes:

Fixes #5530

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[MrFreezeex]

/assign @riverzhang

Maybe @bozzo would also be interested by this PR as he his listed as a maintainer of the kube-router deployment in #5432. I am not sure if I need to assign him to this PR though...

[bozzo]

@MrFreezeex Good Job! It will be easier to update Kube-Router config

[MrFreezeex]

I refactor a lot of my code because kube-router can write into the cni config (updating the subnet), and my previous attempt would overwrite those changes.

I fixed this by allowing the subnet in the cni config to be overwritten by the one retrieved from the host.

I have no more modification to do on this PR, let me know if further changes are needed.

[huxcrux]

LGTM

[Miouge1]

Thanks @MrFreezeex and @bozzo for getting this moving!

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Miouge1, MrFreezeex

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