docs: Add documentation for the mps3-an536 board

Add documentation for the mps3-an536 board type.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240206132931.38376-14-peter.maydell@linaro.org
1 file changed