[OWNERS] Remove kulakowski@, add bwb@

Change-Id: I152526a7eb2a8863eef0ab361a2c8bc64c067680
diff --git a/zircon/system/ulib/ddk/OWNERS b/zircon/system/ulib/ddk/OWNERS
index 0948c9f..20b790e 100644
--- a/zircon/system/ulib/ddk/OWNERS
+++ b/zircon/system/ulib/ddk/OWNERS
@@ -1,4 +1,4 @@
-kulakowski@google.com
+bwb@google.com
 ravoorir@google.com
 teisenbe@google.com
 voydanoff@google.com