Add default code reviewers into OWNERS

Bug: 33166666
Test: gerrit uploader
Change-Id: I3abb630858d394a9891bfb5f576a40ad597a49ef
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..e3c4727
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,2 @@
+# used by Camera2 app
+include platform/packages/apps/Camera2:/OWNERS