dt-bindings: gpio: xilinx: Fix node address in gpio

[ Upstream commit 314c020c ]

Node address doesn't match reg property which is not correct.

Fixes: ba96b2e7 ("dt-bindings: gpio: gpio-xilinx: Convert Xilinx axi gpio binding to YAML")
Signed-off-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>