gpio: brcmstb: Use local variable to access OF node

We already have a local variable that contains a copy of OF node pointer.
Use it instead of dereferencing it again from struct device.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpio-brcmstb.c

@@ -704,7 +704,7 @@ static int brcmstb_gpio_probe(struct platform_device *pdev)
 		}
 
 		gc->owner = THIS_MODULE;
-		gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", dev->of_node);
+		gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", np);
 		if (!gc->label) {
 			err = -ENOMEM;
 			goto fail;