Add stub for GetPonIf

Change-Id: I0a40d0ca5271d49e848466994ab4dc59704b3c40
diff --git a/agent/common/server.cc b/agent/common/server.cc
index f87b85e..0f2e59c 100644
--- a/agent/common/server.cc
+++ b/agent/common/server.cc
@@ -220,6 +220,15 @@
         return EnablePonIf_(request->intf_id());
     }
 
+    Status GetPonIf(
+            ServerContext* context,
+            const openolt::Interface* request,
+            openolt::IntfIndication* response) override {
+
+        // TODO - Return the oper status of the pon interface
+        return Status::OK;
+    }
+
     Status DisablePonIf(
             ServerContext* context,
             const openolt::Interface* request,