plugins exts UPDATE ext callback for data node validation

Fixes #1908
diff --git a/src/plugins_exts/yangdata.c b/src/plugins_exts/yangdata.c
index b2e6f62..38e4c16 100644
--- a/src/plugins_exts/yangdata.c
+++ b/src/plugins_exts/yangdata.c
@@ -171,9 +171,10 @@
         .name = "yang-data",
 
         .plugin.id = "libyang 2 - yang-data, version 1",
-        .plugin.compile = &yangdata_compile,
-        .plugin.sprinter = &yangdata_schema_printer,
+        .plugin.compile = yangdata_compile,
+        .plugin.sprinter = yangdata_schema_printer,
         .plugin.free = yangdata_free,
+        .plugin.node = NULL,
         .plugin.snode = NULL,
         .plugin.validate = NULL
     },