Change var name: cord_provisioned -> on_maas

Change-Id: I046224d3e3297e551f596509367ac39a65fa7fb1
diff --git a/cord-compute-playbook.yml b/cord-compute-playbook.yml
index 0176226..6461e1f 100644
--- a/cord-compute-playbook.yml
+++ b/cord-compute-playbook.yml
@@ -12,7 +12,7 @@
   hosts: all
   become: yes
   roles:
-    - { role: dns-configure, when: not cord_provisioned }
+    - { role: dns-configure, when: not on_maas }
 
 - name: Prep systems
   hosts: compute