pinctrl: ocelot: update pinctrl to automatic base address

struct gpio_chip recommends passing -1 as base to gpiolib. Doing so avoids
conflicts when the chip is external and gpiochip0 already exists.
Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Tested-by: Clément Léger <clement.leger@bootlin.com>
Link: https://lore.kernel.org/r/20211119195928.2498441-3-colin.foster@in-advantage.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-ocelot.c

@@ -1723,7 +1723,7 @@ static int ocelot_gpiochip_register(struct platform_device *pdev,
 	gc = &info->gpio_chip;
 	gc->ngpio = info->desc->npins;
 	gc->parent = &pdev->dev;
-	gc->base = 0;
+	gc->base = -1;
 	gc->of_node = info->dev->of_node;
 	gc->label = "ocelot-gpio";