irqchip/imx-irqsteer: Use devm_platform_ioremap_resource() to simplify code

Use the new helper devm_platform_ioremap_resource() which wraps the
platform_get_resource() and devm_ioremap_resource() together, to
simplify the code.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/irqchip/irq-imx-irqsteer.c

@@ -144,7 +144,6 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct irqsteer_data *data;
-	struct resource *res;
 	u32 irqs_num;
 	int i, ret;
 
@@ -152,8 +151,7 @@ static int imx_irqsteer_probe(struct platform_device *pdev)
 	if (!data)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	data->regs = devm_ioremap_resource(&pdev->dev, res);
+	data->regs = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(data->regs)) {
 		dev_err(&pdev->dev, "failed to initialize reg\n");
 		return PTR_ERR(data->regs);