gpio: idio-16: Define fixed direction of the GPIO lines

The direction of the IDIO-16 GPIO lines is fixed with the first 16 lines
as output and the remaining 16 lines as input. Set the gpio_config
fixed_direction_output member to represent the fixed direction of the
GPIO lines.

Fixes: db022478 ("gpio: idio-16: Migrate to the regmap API")
Reported-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
Closes: https://lore.kernel.org/r/9b0375fd-235f-4ee1-a7fa-daca296ef6bf@nutanix.com


Suggested-by: Michael Walle <mwalle@kernel.org>
Cc: stable@vger.kernel.org # ae495810cffe: gpio: regmap: add the .fixed_direction_output configuration parameter
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20251020-fix-gpio-idio-16-regmap-v2-3-ebeb50e93c33@kernel.org


Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>