This adds the target guide for BBC Micro:bit.
Information is taken from https://wiki.qemu.org/Features/MicroBit
and from hw/arm/nrf51_soc.c.
Signed-off-by: Alexandre Iooss <erdnaxe@crans.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20210621075625.540471-1-erdnaxe@crans.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
