hw/microblaze/s3adsp1800: Rename unimplemented MMIO region as xps_gpio

The machine datasheet mentions the GPIO device as 'xps_gpio'.
Rename it accordingly to easily find its documentation.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Message-Id: <20241105130431.22564-5-philmd@linaro.org>
1 file changed