Call module_object_class_by_name() instead of object_class_by_name()
for objects possibly implemented as module

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-26-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>