Add support pillar to compute4_0

PROD-21206

Change-Id: I4e745ca5b75c54920fa20132a4a76cd34aadf9a2
diff --git a/opencontrail/compute/cluster4_0.yml b/opencontrail/compute/cluster4_0.yml
index 68f8007..8c16c70 100644
--- a/opencontrail/compute/cluster4_0.yml
+++ b/opencontrail/compute/cluster4_0.yml
@@ -1,3 +1,5 @@
+classes:
+  - service.opencontrail.compute.cluster
 applications:
 - opencontrail
 parameters: