With phases/kubelet/WriteConfigToDisk() about to support patches
it is required that the function accepts an io.Writer
where the PatchManager can output to and also a patch directory.
Modify all call sites of the function WriteConfigToDisk()
to properly prepare an pass an io.Writer and patches dir to it.
This results in command phases for init/join/upgrade to pass
the root io.Writer (usually stdout) and the patchesDir populated
either via the config file or --patches flag.
665f66d2bc