Move openshift_node_group to private play

This commit moves call to role to a private/ play
for role symlinks.

playbooks/openshift-master/openshift_node_config.yml

@@ -1,4 +0,0 @@
----
-- import_playbook: ../init/main.yml
-
-- import_playbook: private/openshift_node_config.yml

playbooks/openshift-master/openshift_node_group.yml

@@ -5,8 +5,4 @@
     l_openshift_version_set_hosts: "all:!all"
     l_sanity_check_hosts: "{{ groups['oo_masters_to_config'] }}"
 
-- name: Setup node-group configmaps
-  hosts: oo_first_master
-  tasks:
-  - import_role:
-      name: openshift_node_group
+- import_playbook: private/openshift_node_group.yml