clk: sunxi-ng: sun9i-a80: Fix wrong pointer passed to PTR_ERR()

PTR_ERR should access the value just tested by IS_ERR, otherwise
the wrong error code will be returned.

Fixes: 783ab76a ("clk: sunxi-ng: Add A80 Display Engine CCU")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/sunxi-ng/ccu-sun9i-a80-de.c

@@ -232,7 +232,7 @@ static int sun9i_a80_de_clk_probe(struct platform_device *pdev)
 
 	rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
 	if (IS_ERR(rstc)) {
-		ret = PTR_ERR(bus_clk);
+		ret = PTR_ERR(rstc);
 		if (ret != -EPROBE_DEFER)
 			dev_err(&pdev->dev,
 				"Couldn't get reset control: %d\n", ret);