gpio: tb10x: fix return value check in tb10x_gpio_probe()

In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR(). Also remove the dev_err call to avoid redundant
error message.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-tb10x.c

@@ -207,10 +207,8 @@ static int tb10x_gpio_probe(struct platform_device *pdev)
 	spin_lock_init(&tb10x_gpio->spinlock);
 
 	tb10x_gpio->base = devm_ioremap_resource(&pdev->dev, mem);
-	if (!tb10x_gpio->base) {
-		dev_err(&pdev->dev, "Could not remap reg space.\n");
-		goto fail_ioremap;
-	}
+	if (IS_ERR(tb10x_gpio->base))
+		return PTR_ERR(tb10x_gpio->base);
 
 	tb10x_gpio->gc.label		= of_node_full_name(dn);
 	tb10x_gpio->gc.dev		= &pdev->dev;