pinctrl: starfive: jh7100: use new GPIO line value setter callbacks

struct gpio_chip now has callbacks for setting line values that return
an integer, allowing to indicate failures. Convert the driver to using
them.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Hal Feng <hal.feng@starfivetech.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Link: https://lore.kernel.org/20250612-gpiochip-set-rv-pinctrl-starfive-v1-1-8507b46516f5@linaro.org


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