Uses the logic introduced in the previous patch to convert all
kubernetes/preinstall/vars/* os specific files to the `pkgs`
dictionary.
Some niceties for devs:
- always validate the `pkgs` variable to catch mistakes in CI.
- ensure that `pkgs` is always sorted. This makes it easier to find the
packages you're looking for.
According to the canal github[1] the repo is not maintained over 5 years.
In addition, the README says
```
Originally, we thought we might more deeply integrate the two projects
(possibly even going as far as a rebranding!). However, over time it
became clear that that wasn't really necessary to fulfil our goal of
making them work well together. Ultimately, we decided to focus on
adding features to both projects rather than doing work just to
combine them.
```
So it is difficult to support canal by Kubespray at this situation.
[1]: https://github.com/projectcalico/canal
