Fix mountflags and kubelet config

Add missing --require-kubeconfig to the if..else stanza.
Make sure certs dirs mounted in RO.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

roles/network_plugin/flannel/templates/flannel-pod.yml

@@ -33,6 +33,7 @@
             mountPath: "/run/flannel"
           - name: "etcd-certs"
             mountPath: "{{ etcd_cert_dir }}"
+            readOnly: true
         securityContext:
           privileged: true
     hostNetwork: true