pinctrl: st: Switch to use fwnode instead of of_node

The OF node in the GPIO library is deprecated and soon
will be removed.

GPIO library now accepts fwnode as a firmware node, so
switch the driver to use it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/20221010075615.43244-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-st.c

@@ -1175,7 +1175,7 @@ static int st_pctl_dt_calculate_pin(struct st_pinctrl *info,
 
 	for (i = 0; i < info->nbanks; i++) {
 		chip = &info->banks[i].gpio_chip;
-		if (chip->of_node == np) {
+		if (chip->fwnode == of_fwnode_handle(np)) {
 			if (offset < chip->ngpio)
 				retval = chip->base + offset;
 			break;
@@ -1518,7 +1518,7 @@ static int st_gpiolib_register_bank(struct st_pinctrl *info,
 	bank->gpio_chip = st_gpio_template;
 	bank->gpio_chip.base = bank_num * ST_GPIO_PINS_PER_BANK;
 	bank->gpio_chip.ngpio = ST_GPIO_PINS_PER_BANK;
-	bank->gpio_chip.of_node = np;
+	bank->gpio_chip.fwnode = of_fwnode_handle(np);
 	bank->gpio_chip.parent = dev;
 	spin_lock_init(&bank->lock);