spi: sprd-adi: checking for NULL instead of IS_ERR()

devm_ioremap_resource() returns error pointers, it never returns NULL.

Fixes: 7e2903cb ("spi: Add ADI driver for Spreadtrum platform")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

drivers/spi/spi-sprd-adi.c

@@ -341,8 +341,8 @@ static int sprd_adi_probe(struct platform_device *pdev)
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	sadi->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!sadi->base) {
-		ret = -ENOMEM;
+	if (IS_ERR(sadi->base)) {
+		ret = PTR_ERR(sadi->base);
 		goto put_ctlr;
 	}