hw/arm/mps2-tz: Add new mps3-an547 board

Add support for the mps3-an547 board; this is an SSE-300 based
FPGA image that runs on the MPS3.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210219144617.4782-43-peter.maydell@linaro.org