rtc: pl031: fix resource leak in pl031_probe

When devm_rtc_allocate_device is failed in pl031_probe, it should release
mem regions with device.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng Liang <zhengliang6@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20201112093139.32566-1-zhengliang6@huawei.com

drivers/rtc/rtc-pl031.c

@@ -361,8 +361,10 @@ static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 
 	device_init_wakeup(&adev->dev, true);
 	ldata->rtc = devm_rtc_allocate_device(&adev->dev);
-	if (IS_ERR(ldata->rtc))
-		return PTR_ERR(ldata->rtc);
+	if (IS_ERR(ldata->rtc)) {
+		ret = PTR_ERR(ldata->rtc);
+		goto out;
+	}
 
 	ldata->rtc->ops = ops;
 	ldata->rtc->range_min = vendor->range_min;