qapi: Allow enums in anonymous unions

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index c129697..df9f7fb 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -263,7 +263,8 @@
     for key in members:
         assert (members[key] in builtin_types
             or find_struct(members[key])
-            or find_union(members[key])), "Invalid anonymous union member"
+            or find_union(members[key])
+            or find_enum(members[key])), "Invalid anonymous union member"
 
         enum_full_value = generate_enum_full_value(disc_type, key)
         ret += mcgen('''