Move kubernetes/master to kubernetes/control-plane (#7218)

This is a small step to replace "master" with "control-plane" in
Kubespray project.

roles/kubernetes/control-plane/tasks/kubeadm-version.yml

@@ -0,0 +1,15 @@
+---
+- name: Get the kubeadm version
+  command: "{{ bin_dir }}/kubeadm version -o short"
+  register: kubeadm_output
+  changed_when: false
+
+- name: Set kubeadm api version to v1beta2
+  set_fact:
+    kubeadmConfig_api_version: v1beta2
+
+- name: kubeadm | Create kubeadm config
+  template:
+    src: "kubeadm-config.{{ kubeadmConfig_api_version }}.yaml.j2"
+    dest: "{{ kube_config_dir }}/kubeadm-config.yaml"
+    mode: 0640