net: mido: mdio-mux-bcm-iproc: Use devm_platform_get_and_ioremap_resource()

Use devm_platform_get_and_ioremap_resource() to simplify
code and avoid a null-ptr-deref by checking 'res' in it.
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/mdio/mdio-mux-bcm-iproc.c

@@ -187,7 +187,9 @@ static int mdio_mux_iproc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	md->dev = &pdev->dev;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	md->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+	if (IS_ERR(md->base))
+		return PTR_ERR(md->base);
 	if (res->start & 0xfff) {
 		/* For backward compatibility in case the
 		 * base address is specified with an offset.
@@ -196,9 +198,6 @@ static int mdio_mux_iproc_probe(struct platform_device *pdev)
 		res->start &= ~0xfff;
 		res->end = res->start + MDIO_REG_ADDR_SPACE_SIZE - 1;
 	}
-	md->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(md->base))
-		return PTR_ERR(md->base);
 
 	md->mii_bus = devm_mdiobus_alloc(&pdev->dev);
 	if (!md->mii_bus) {