gpio: ts5500: Use platform_get_irq() to get the interrupt

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypassed the hierarchical setup and messed up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq().
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpio-ts5500.c

@@ -317,22 +317,19 @@ static int ts5500_dio_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	const char *name = dev_name(dev);
 	struct ts5500_priv *priv;
-	struct resource *res;
 	unsigned long flags;
 	int ret;
 
-	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!res) {
-		dev_err(dev, "missing IRQ resource\n");
-		return -EINVAL;
-	}
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0)
+		return ret;
 
 	priv = devm_kzalloc(dev, sizeof(struct ts5500_priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
 	platform_set_drvdata(pdev, priv);
-	priv->hwirq = res->start;
+	priv->hwirq = ret;
 	spin_lock_init(&priv->lock);
 
 	priv->gpio_chip.owner = THIS_MODULE;