numa: Flatten simple union NumaOptions

Simple unions are simpler than flat unions in the schema, but more
complicated in C and on the QMP wire: there's extra indirection in C
and extra nesting on the wire, both pointless.  They're best avoided
in new code.

NumaOptions isn't new, but it's only used internally, not in QMP.
Convert it to a flat union.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1487709988-14322-2-git-send-email-armbru@redhat.com>
diff --git a/numa.c b/numa.c
index 9f56be9..e01cb54 100644
--- a/numa.c
+++ b/numa.c
@@ -228,8 +228,8 @@
     }
 
     switch (object->type) {
-    case NUMA_OPTIONS_KIND_NODE:
-        numa_node_parse(object->u.node.data, opts, &err);
+    case NUMA_OPTIONS_TYPE_NODE:
+        numa_node_parse(&object->u.node, opts, &err);
         if (err) {
             goto end;
         }