[VOL-2968] Update protos/Makefile to include common.proto

Change-Id: I317df11b31c4265a169e3fe3ae5137653afdefcc
diff --git a/agent/Makefile.in b/agent/Makefile.in
index 0e4bded..a5407ea 100644
--- a/agent/Makefile.in
+++ b/agent/Makefile.in
@@ -42,7 +42,7 @@
 # This specifies the GIT tag in https://github.com/opencord/voltha-protos
 # repo that we need to refer to, to pick the right version of
 # openolt.proto and tech_profile.proto
-OPENOLT_PROTO_VER ?= v3.1.0
+OPENOLT_PROTO_VER ?= v3.3.4
 
 #
 # Build directory