hmp: info spice: Show string channel name Useful for debugging. https://bugzilla.redhat.com/show_bug.cgi?id=822418 Signed-off-by: Cole Robinson <crobinso@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>