cirrus: cs89x0: 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/cirrus/cs89x0.c

@@ -1845,7 +1845,6 @@ static int __init cs89x0_platform_probe(struct platform_device *pdev)
 {
 	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
 	struct net_local *lp;
-	struct resource *mem_res;
 	void __iomem *virt_addr;
 	int err;
 
@@ -1861,8 +1860,7 @@ static int __init cs89x0_platform_probe(struct platform_device *pdev)
 		goto free;
 	}
 
-	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	virt_addr = devm_ioremap_resource(&pdev->dev, mem_res);
+	virt_addr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(virt_addr)) {
 		err = PTR_ERR(virt_addr);
 		goto free;