create systemd drop-in path if not existent

roles/network_plugin/flannel/tasks/main.yml

@@ -70,6 +70,13 @@
     - Flannel | restart docker
   when: ansible_service_mgr in ["sysvinit","upstart"]
 
+- name: Flannel | Ensure path for docker network systemd drop-in
+  file:
+    path: "/etc/systemd/system/docker.service.d"
+    state: directory
+    owner: root
+  when: ansible_service_mgr == "systemd"
+
 - name: Flannel | Create docker network systemd drop-in
   template:
     src: flannel-options.conf.j2