The 'debian' dockerfile was deprecated in favour of versioned
dockerfiles in July 2017. That is enough time for developers to
be warned about the rename.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>