[VOL-3080] Introducing Mac Learning application in voltha-onos image

Aso moving to 2.2-latest to get all the recent changes introduced in olt pipeliner.

Change-Id: I3ac6984f0be0b8660afbcf9c721e3db575b2a6ad
diff --git a/Dockerfile.voltha-onos b/Dockerfile.voltha-onos
index 9403491..941226b 100644
--- a/Dockerfile.voltha-onos
+++ b/Dockerfile.voltha-onos
@@ -34,7 +34,7 @@
 
 
 # Unpack and install specific apps from download stage
-FROM onosproject/onos:2.2.2 as install
+FROM onosproject/onos:2.2-latest as install
 
 # The ENV settings must be replicated below as they are not shared between stages
 ENV ONOS=/root/onos
@@ -58,7 +58,7 @@
 
 
 # Create the final image coping over the installed applications from the install stage
-FROM onosproject/onos:2.2.2
+FROM onosproject/onos:2.2-latest
 
 # The ENV settings must be replicated below as they are not shared between stages
 ENV ONOS=/root/onos