Disabling by default the atomix persistency for ONOS in the voltha-infra chart

Change-Id: I489f5f1a1d525ad6ea59aabe0850bdaa6270707e
diff --git a/voltha-infra/values.yaml b/voltha-infra/values.yaml
index 6c6676c..208b0b3 100644
--- a/voltha-infra/values.yaml
+++ b/voltha-infra/values.yaml
@@ -21,6 +21,8 @@
   replicas: 1
   atomix:
     replicas: 0
+    persistence:
+      enabled: false
   image:
     pullPolicy: Always
     repository: voltha/voltha-onos