spi: mxs: 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/20190904135918.25352-19-yuehaibing@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-mxs.c

@@ -532,7 +532,6 @@ static int mxs_spi_probe(struct platform_device *pdev)
 	struct spi_master *master;
 	struct mxs_spi *spi;
 	struct mxs_ssp *ssp;
-	struct resource *iores;
 	struct clk *clk;
 	void __iomem *base;
 	int devid, clk_freq;
@@ -545,12 +544,11 @@ static int mxs_spi_probe(struct platform_device *pdev)
 	 */
 	const int clk_freq_default = 160000000;
 
-	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq_err = platform_get_irq(pdev, 0);
 	if (irq_err < 0)
 		return irq_err;
 
-	base = devm_ioremap_resource(&pdev->dev, iores);
+	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
 		return PTR_ERR(base);