SEBA-83 Support persistent storage that mounts a filesystem, such as rook/ceph

Change-Id: I6823094ff82d820bbfdcd7ec834a2d08d983981f
diff --git a/xos-core/templates/db-deployment.yaml b/xos-core/templates/db-deployment.yaml
index 82f1507..d2cb923 100644
--- a/xos-core/templates/db-deployment.yaml
+++ b/xos-core/templates/db-deployment.yaml
@@ -43,6 +43,8 @@
                 secretKeyRef:
                   name: xos-db-secrets
                   key: password
+            - name: PGDATA
+              value: "/var/lib/postgresql/data/pgdata"
       {{- if .Values.needDBPersistence }}
           volumeMounts:
             - name: db-pv-storage