Change var name: cord_provisioned -> on_maas

Change-Id: I046224d3e3297e551f596509367ac39a65fa7fb1
diff --git a/vars/cord_single_defaults.yml b/vars/cord_single_defaults.yml
index cb21344..e5890d4 100644
--- a/vars/cord_single_defaults.yml
+++ b/vars/cord_single_defaults.yml
@@ -3,7 +3,7 @@
 
 # For a single-node case, we don't expect the node to already have been
 # provisioned by CORD MaaS.  It's just Ubuntu 14.04.
-cord_provisioned: False
+on_maas: False
 
 openstack_version: kilo