Add default code reviewers into OWNERS

Bug: 33166666
Test: gerrit uploader
Change-Id: I8bc5ffa4ea334b801688ebbc0e55503dadecc517
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..210028e
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,2 @@
+include platform/libcore:/OWNERS
+iam@google.com