List the 'tosa' machine with the XScale-based PDAs models.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20201120173953.2539469-5-f4bug@amsat.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>