topo: fix proto path
diff --git a/go/svc/topo/config.proto b/go/svc/topo/config.proto
index f1054be..33aadbe 100644
--- a/go/svc/topo/config.proto
+++ b/go/svc/topo/config.proto
@@ -1,5 +1,7 @@
 syntax = "proto3";
 
+package proto;
+
 message Config {
     repeated Switch switch = 1;
     repeated Machine machine = 2;