commit ba43d28916c4f51c19bd7366089155ce81bee058 introduces a bug:
The stream-not-found case doesn't error out any more, instead the
code silently uses the first stream. Fix it.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>