gpiolib: of: remove gpio_to_desc() usage

As demonstrated by commit
390d82e3
"gpiolib: ACPI: remove gpio_to_desc() usage"

gpio_to_desc() must die. Replace one of its usage by the
newly-introduced gpiochip_get_desc() function.
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-of.c

@@ -48,7 +48,7 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data)
 	if (ret < 0)
 		return false;
 
-	gg_data->out_gpio = gpio_to_desc(ret + gc->base);
+	gg_data->out_gpio = gpiochip_get_desc(gc, ret);
 	return true;
 }