Add shell script to patch configmap for kube-proxy

Signed-off-by: michal.gubricky <michal.gubricky@dnation.cloud>

providers/openstack/scs/cluster-class/templates/kubeadm-control-plane-template.yaml

@@ -14,11 +14,11 @@ spec:
             extraArgs:
               cloud-provider: external
               bind-address: 0.0.0.0
-              secure-port: 10257
+              secure-port: "10257"
           scheduler:
             extraArgs:
               bind-address: 0.0.0.0
-              secure-port: 10259
+              secure-port: "10259"
           etcd:
             local:
               dataDir: /var/lib/etcd
@@ -29,6 +29,54 @@ spec:
                 election-timeout: "2500"
                 heartbeat-interval: "250"
                 snapshot-count: "6400"
+        files:
+        - content: |
+            ---
+            apiVersion: kubeproxy.config.k8s.io/v1alpha1
+            kind: KubeProxyConfiguration
+            metricsBindAddress: "0.0.0.0:10249"
+          path: /etc/kube-proxy-config.yaml
+        - content: |
+            #!/usr/bin/env bash
+
+            #
+            # (PK) I couldn't find a better/simpler way to conifgure it. See:
+            # https://github.com/kubernetes-sigs/cluster-api/issues/4512
+            #
+
+            set -o errexit
+            set -o nounset
+            set -o pipefail
+
+            dir=$( cd "$( dirname "$${BASH_SOURCE[0]}" )" && pwd )
+            readonly dir
+
+            # Exit fast if already appended.
+            if [[ ! -f $${dir}/kube-proxy-config.yaml ]]; then
+              exit 0
+            fi
+
+            # kubeadm config is in different directory in Flatcar (/etc) and Ubuntu (/run/kubeadm).
+            kubeadm_file="/etc/kubeadm.yml"
+            if [[ ! -f $${kubeadm_file} ]]; then
+              kubeadm_file="/run/kubeadm/kubeadm.yaml"
+            fi
+
+            # Run this script only if this is the init node.
+            if [[ ! -f $${kubeadm_file} ]]; then
+              exit 0
+            fi
+
+            # Append kube-proxy-config.yaml to kubeadm config and delete it
+            cat "$${dir}/kube-proxy-config.yaml" >> "$${kubeadm_file}"
+            rm "$${dir}/kube-proxy-config.yaml"
+
+            echo success > /tmp/kube-proxy-patch
+          owner: root:root
+          path: /etc/kube-proxy-patch.sh
+          permissions: "0755"
+        preKubeadmCommands:
+        - bash /etc/kube-proxy-patch.sh
         initConfiguration:
           nodeRegistration:
             kubeletExtraArgs: