* refactor(init): Allow kubeadm init on controlplane
This shifts the cluster formation from init(bootstrap) and join(control plane)
to init(control plane).
This makes use of the previously implemented initToken to provide a TTL for
cluster initialization to take place and allows us to mostly treat all control
plane nodes equal. This also sets up the path for us to handle master upgrades
and not be concerned with odd behavior when upgrading the previously defined
init node.
To facilitate kubeadm init across all control plane nodes, we make use of the
initToken to run `kubeadm init phase certs` command to generate any missing
certificates once. All other control plane nodes will attempt to sync the
necessary certs/files via all defined trustd endpoints and being the startup
process.
* feat(init): Add service runner context to PreFunc
Signed-off-by: Brad Beam <brad.beam@talos-systems.com>
