gpio: spacemit: add support for K1 SoC

Implement GPIO functionality which capable of setting pin as
input, output. Also, each pin can be used as interrupt which
support rising, falling, or both edge type trigger.

Reviewed-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250412-03-k1-gpio-v8-2-1c6862d272ec@gentoo.org


Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>