net: dsa: vsc73xx: convert to devm_platform_ioremap_resource

Use the helper function that wraps the calls to platform_get_resource()
and devm_ioremap_resource() together.

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/dsa/vitesse-vsc73xx-platform.c

···
 {
 	struct device *dev = &pdev->dev;
 	struct vsc73xx_platform *vsc_platform;
-	struct resource *res = NULL;
 	int ret;
 
 	vsc_platform = devm_kzalloc(dev, sizeof(*vsc_platform), GFP_KERNEL);
···
 	vsc_platform->vsc.ops = &vsc73xx_platform_ops;
 
 	/* obtain I/O memory space */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
-		ret = -ENXIO;
-		return ret;
-	}
-
-	vsc_platform->base_addr = devm_ioremap_resource(&pdev->dev, res);
+	vsc_platform->base_addr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(vsc_platform->base_addr)) {
 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
 		ret = -ENXIO;