Change var name: cord_provisioned -> on_maas

Change-Id: I046224d3e3297e551f596509367ac39a65fa7fb1
(cherry picked from commit fc43e8441f77ce9fbd5be13a7da7e98e529b9353)
diff --git a/cord-head-playbook.yml b/cord-head-playbook.yml
index 0f7b930..7b9fac6 100644
--- a/cord-head-playbook.yml
+++ b/cord-head-playbook.yml
@@ -15,15 +15,15 @@
   hosts: head
   become: yes
   roles:
-    - { role: dns-nsd, when: not cord_provisioned }
-    - { role: dns-unbound, when: not cord_provisioned }
+    - { role: dns-nsd, when: not on_maas }
+    - { role: dns-unbound, when: not on_maas }
     - apt-cacher-ng
 
 - name: Configure all hosts to use DNS server
   hosts: all
   become: yes
   roles:
-    - { role: dns-configure, when: not cord_provisioned }
+    - { role: dns-configure, when: not on_maas }
 
 - name: Prep systems
   hosts: all
@@ -51,5 +51,5 @@
 - name: Set up Automated Compute Node Provisioning
   hosts: head
   roles:
-    - { role: automation-integration, when on_maas }
+    - { role: automation-integration, when: on_maas }