[owners] Fix protobuf owners

Cross-repo OWNERS includes don't actually work :(

Change-Id: I0e8f7d527df8b1a3f529c6d373122fdeea6c5273
diff --git a/OWNERS b/OWNERS
index bdb6886..a77d274 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1,2 +1,6 @@
-# Maintained by Cobalt team
-include /src/cobalt/OWNERS
\ No newline at end of file
+azani@google.com
+camrdale@google.com
+ninai@google.com
+pesk@google.com
+stevefung@google.com
+zmbush@google.com
\ No newline at end of file