K8s control plane is deployed by KubeadmControlPlane controller. This
controller creates CAPI machines and infrastructure objects
(Metal3Machine). Metal3Machine objects are created based on a template
which contins host selector label. Control plane label is assigned to a
particular BareMetalHots object defined inside of the shared
kustomization.
Relates-To: #149
Closes: #221
Change-Id: I3be1750aacf9736ece2944045c036f405e404561
df2fff0acf