gpio: altera: Add missed base and label initialisations

During conversion driver to modern APIs the base field initial value
of the GPIO chip was moved from -1 to 0, which triggers a warning.
Add missed base initialisation as it was in the original code.

Initialise the GPIO chip label correctly as it was done by
of_mm_gpiochip_add_data() before the below mentioned change.

Fixes: 50dded8 ("gpio: altera: Drop legacy-of-mm-gpiochip.h header")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241118095402.516989-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Author: andy-shev

drivers/gpio/gpio-altera.c

@@ -261,6 +261,11 @@ static int altera_gpio_probe(struct platform_device *pdev)
 	altera_gc->gc.set		= altera_gpio_set;
 	altera_gc->gc.owner		= THIS_MODULE;
 	altera_gc->gc.parent		= &pdev->dev;
+	altera_gc->gc.base		= -1;
+
+	altera_gc->gc.label = devm_kasprintf(dev, GFP_KERNEL, "%pfw", dev_fwnode(dev));
+	if (!altera_gc->gc.label)
+		return -ENOMEM;
 
 	altera_gc->regs = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(altera_gc->regs))