regulator: don't compare raw GPIO descriptor pointers

There's no API contract saying that two GPIO descriptor pointers
obtained with a call to gpiod_get() (or one of the variants), that refer
to the same physical GPIO pin, always point to the same structure. Use
the dedicated comparator function.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://patch.msgid.link/20250407-gpiod-is-equal-v1-2-7d85f568ae6e@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Bartosz Golaszewski

drivers/regulator/core.c

@@ -2617,7 +2617,7 @@ static int regulator_ena_gpio_request(struct regulator_dev *rdev,
 	mutex_lock(&regulator_list_mutex);
 
 	list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
-		if (pin->gpiod == gpiod) {
+		if (gpiod_is_equal(pin->gpiod, gpiod)) {
 			rdev_dbg(rdev, "GPIO is already used\n");
 			goto update_ena_gpio_to_rdev;
 		}