Using released versions for VOLTHA-2.5

Change-Id: I6b2ebe96a45c4c16495ee8a9be011d194e9e47e7
diff --git a/voltha-adapter-openonu/values.yaml b/voltha-adapter-openonu/values.yaml
index 4558ddf..6917202 100644
--- a/voltha-adapter-openonu/values.yaml
+++ b/voltha-adapter-openonu/values.yaml
@@ -64,7 +64,7 @@
   adapter_open_onu:
     registry: '{{ .Values.defaults.image_registry }}'
     repository: '{{ .Values.defaults.image_org }}voltha-openonu-adapter'
-    tag: '{{- if hasKey .Values.defaults "image_tag" }}{{- if .Values.defaults.image_tag }}{{ .Values.defaults.image_tag }}{{- else }}2.4.0{{- end }}{{- else }}2.4.0{{- end }}'
+    tag: '{{- if hasKey .Values.defaults "image_tag" }}{{- if .Values.defaults.image_tag }}{{ .Values.defaults.image_tag }}{{- else }}2.5.0{{- end }}{{- else }}2.5.0{{- end }}'
     pullPolicy: '{{ .Values.defaults.image_pullPolicy }}'
   adapter_open_onu_go:
     repository: '{{ .Values.defaults.image_org }}voltha-openonu-adapter-go'