Commit 4e99f4b12c0 (qapi: Drop simple unions) eliminated implicitly
defined union branch types, except for the empty object type
'q_empty'. QAPISchemaGenRSTVisitor._nodes_for_members() still has
code to generate documentation for implicitly defined union branch
types. It does nothing for 'q_empty'. Simplify.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240216145841.2099240-5-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
e51e80ccf6