spi: lp-8841: 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>
Link: https://lore.kernel.org/r/20190904135918.25352-15-yuehaibing@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-lp8841-rtc.c

@@ -185,7 +185,6 @@ spi_lp8841_rtc_probe(struct platform_device *pdev)
 	int				ret;
 	struct spi_master		*master;
 	struct spi_lp8841_rtc		*data;
-	void				*iomem;
 
 	master = spi_alloc_master(&pdev->dev, sizeof(*data));
 	if (!master)
@@ -207,8 +206,7 @@ spi_lp8841_rtc_probe(struct platform_device *pdev)
 
 	data = spi_master_get_devdata(master);
 
-	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	data->iomem = devm_ioremap_resource(&pdev->dev, iomem);
+	data->iomem = devm_platform_ioremap_resource(pdev, 0);
 	ret = PTR_ERR_OR_ZERO(data->iomem);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to get IO address\n");