This image isn't going to build anything significant as it is just
intended for building test cases. In case it does end up getting
inadvertently included in a build lets aim for the minimal possible
product.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
be5e1f527a