gather facts from all instances, maybe include calico-rr

cluster.yml

@@ -26,7 +26,7 @@
       setup:
       delegate_to: "{{item}}"
       delegate_facts: True
-      with_items: "{{ groups['k8s-cluster'] + groups['etcd'] + groups['calico-rr'] }}"
+      with_items: "{{ groups['k8s-cluster'] + groups['etcd'] + groups['calico-rr']|default([]) }}"
 
 - hosts: k8s-cluster:etcd:calico-rr
   any_errors_fatal: "{{ any_errors_fatal | default(true) }}"