gpio: deprecate devm_gpiod_unhinge()

This function was introduced as a workaround for an issue with resource
ownership in the regulator subsystem. Rather than passing the ownership
of a GPIO, we should make the regulator core be able to deal with
resources it didn't request. Deprecate this function so that we don't
get more users in the tree.

Link: https://lore.kernel.org/r/20250401-gpio-todo-remove-nonexclusive-v2-2-7c1380797b0d@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpiolib-devres.c

@@ -317,11 +317,15 @@ EXPORT_SYMBOL_GPL(devm_gpiod_put);
  * @dev:	GPIO consumer
  * @desc:	GPIO descriptor to remove resource management from
  *
+ * *DEPRECATED*
+ * This function should not be used. It's been provided as a workaround for
+ * resource ownership issues in the regulator framework and should be replaced
+ * with a better solution.
+ *
  * Remove resource management from a GPIO descriptor. This is needed when
  * you want to hand over lifecycle management of a descriptor to another
  * mechanism.
  */
-
 void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
 {
 	int ret;