ASoC: sun8i-codec: 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: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190727150738.54764-35-yuehaibing@huawei.comSigned-off-by: NMark Brown <broonie@kernel.org>

sound/soc/sunxi/sun8i-codec.c

@@ -533,7 +533,6 @@ static const struct regmap_config sun8i_codec_regmap_config = {
 
 static int sun8i_codec_probe(struct platform_device *pdev)
 {
-	struct resource *res_base;
 	struct sun8i_codec *scodec;
 	void __iomem *base;
 	int ret;
@@ -556,8 +555,7 @@ static int sun8i_codec_probe(struct platform_device *pdev)
 		return PTR_ERR(scodec->clk_bus);
 	}
 
-	res_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	base = devm_ioremap_resource(&pdev->dev, res_base);
+	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base)) {
 		dev_err(&pdev->dev, "Failed to map the registers\n");
 		return PTR_ERR(base);