Update to last version of wdef_schemas

diff --git a/wdef_schemas b/wdef_schemas
index 2ce6ffd0bfe427f340a60734db38fa3c138446bb..7b9ce8516bf5c9bed8226f9e974a65dfd4ea7878 160000 (submodule)
--- a/wdef_schemas
+++ b/wdef_schemas
@@ -1 +1 @@
-Subproject commit 2ce6ffd0bfe427f340a60734db38fa3c138446bb
+Subproject commit 7b9ce8516bf5c9bed8226f9e974a65dfd4ea7878