dt-bindings: pinctrl: Add support for canaan,k230 SoC

Add device tree binding details for Canaan K230 pinctrl device.

Signed-off-by: Ze Huang <18771902331@163.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/20240926-k230-pinctrl-v2-1-a9a36fba4b34@163.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>