mmc: sdhci-of-aspeed: Fix return value check in aspeed_sdc_probe()

In case of error, the function of_platform_device_create() returns
NULL pointer not ERR_PTR(). The IS_ERR() test in the return value
check should be replaced with NULL test.
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-of-aspeed.c

@@ -261,9 +261,9 @@ static int aspeed_sdc_probe(struct platform_device *pdev)
 		struct platform_device *cpdev;
 
 		cpdev = of_platform_device_create(child, NULL, &pdev->dev);
-		if (IS_ERR(cpdev)) {
+		if (!cpdev) {
 			of_node_put(child);
-			ret = PTR_ERR(cpdev);
+			ret = -ENODEV;
 			goto err_clk;
 		}
 	}