Add run_once to define calico pool task name

roles/network_plugin/calico/tasks/main.yml

@@ -63,6 +63,7 @@
   when: nat_outgoing|default(false) and not peer_with_router|default(false)
 
 - name: Calico | Define calico pool task name
+  run_once: true
   set_fact:
     pool_task_name: "with options {{ ipip_arg|default('') }} {{ nat_arg|default('') }}"
   when: ipip_arg|default(false) or nat_arg|default(false)