Make it possible to run k0s with only the kernel as a dependency

[phroggyy]

As MKE should be able to run on any Linux kernel, we don't want any hard dependencies. Currently, the kubelet has some hard dependencies, as documented in https://github.com/Mirantis/mke/blob/main/docs/internal/host-dependencies.md.

We should aim to remove all non-kernel dependencies, either through bundling more things into mke or, preferably, contribute to upstream where possible to remove those dependencies.

Spawned from #176

[mikhail-sakhnov]

The next step could be run it as unikernel bootable thing

[ncopa]

I think to solve this we can run mke in an empty docker container. It should help us identify all the needed OS userspace dependencies.

[ncopa]

Related upstream PR to remove external find, nice and du dependencies:
kubernetes/kubernetes#96115

[ncopa]

the kubernetes/kubernetes#96115 has been merged upstream which means that with kubernetes 1.22 we only need iptables.