Using latest voltha-openonu-go with fixed omci-lib-go for extended PMs

Change-Id: I4695ab754527f2665f2731b22eeff077d64b9d84
diff --git a/voltha-stack/Chart.yaml b/voltha-stack/Chart.yaml
index 0c83a64..9205f9f 100644
--- a/voltha-stack/Chart.yaml
+++ b/voltha-stack/Chart.yaml
@@ -28,7 +28,7 @@
 name: voltha-stack
 
 appVersion: "2.8"
-version: 2.8.0
+version: 2.8.1
 
 dependencies:
   - name: voltha
@@ -37,7 +37,7 @@
     condition: voltha.enabled
   - name: voltha-adapter-openonu
     repository: file://../voltha-adapter-openonu
-    version: 2.8.5
+    version: 2.8.6
     condition: voltha-adapter-openonu.enabled
   - name: voltha-adapter-openolt
     repository: file://../voltha-adapter-openolt