net: mvneta: use devm_platform_ioremap_resource() to simplify code

Use devm_platform_ioremap_resource() to simplify the code a bit.
This is detected by coccinelle.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvneta_bm.c

@@ -411,15 +411,13 @@ static int mvneta_bm_probe(struct platform_device *pdev)
 {
 	struct device_node *dn = pdev->dev.of_node;
 	struct mvneta_bm *priv;
-	struct resource *res;
 	int err;
 
 	priv = devm_kzalloc(&pdev->dev, sizeof(struct mvneta_bm), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	priv->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	priv->reg_base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->reg_base))
 		return PTR_ERR(priv->reg_base);