dt-bindings: gpio: Add Tegra238 support

dt-bindings: gpio: Add Tegra238 support

Extend the existing Tegra186 GPIO controller device tree bindings with
support for the GPIO controllers found on Tegra238. Tegra238 has two
GPIO controllers: the main controller and always-on (AON) controller.
The number of pins is slightly different, but the programming model
remains the same.

Add a new header, include/dt-bindings/gpio/nvidia,tegra238-gpio.h,
that defines port IDs as well as the TEGRA238_MAIN_GPIO() helper,
both of which are used in conjunction to create a unique specifier
for each pin.

Signed-off-by: Prathamesh Shete <pshete@nvidia.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260514124835.108532-1-pshete@nvidia.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>