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/defaults/main/etcd.yml

@@ -0,0 +1,27 @@
+---
+# Note: This does not set up DNS entries. It simply adds the following DNS
+# entries to the certificate
+etcd_cert_alt_names:
+  - "etcd.kube-system.svc.{{ dns_domain }}"
+  - "etcd.kube-system.svc"
+  - "etcd.kube-system"
+  - "etcd"
+etcd_cert_alt_ips: []
+
+etcd_heartbeat_interval: "250"
+etcd_election_timeout: "5000"
+
+# etcd_snapshot_count: "10000"
+
+etcd_metrics: "basic"
+
+## A dictionary of extra environment variables to add to etcd.env, formatted like:
+##  etcd_extra_vars:
+##    var1: "value1"
+##    var2: "value2"
+## Note this is different from the etcd role with ETCD_ prfexi, caps, and underscores
+etcd_extra_vars: {}
+
+# etcd_quota_backend_bytes: "2147483648"
+
+etcd_compaction_retention: "8"