rtc: sunplus: fix return value in sp_rtc_probe()

If devm_ioremap_resource() fails, it should return error
code from sp_rtc->reg_base in sp_rtc_probe().

Fixes: fad6cbe ("rtc: Add driver for RTC in Sunplus SP7021")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20220106075711.3216468-1-yangyingliang@huawei.com

Author: Yang Yingliang

drivers/rtc/rtc-sunplus.c

@@ -238,7 +238,7 @@ static int sp_rtc_probe(struct platform_device *plat_dev)
 	sp_rtc->res = platform_get_resource_byname(plat_dev, IORESOURCE_MEM, RTC_REG_NAME);
 	sp_rtc->reg_base = devm_ioremap_resource(&plat_dev->dev, sp_rtc->res);
 	if (IS_ERR(sp_rtc->reg_base))
-		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->res),
+		return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->reg_base),
 					    "%s devm_ioremap_resource fail\n", RTC_REG_NAME);
 	dev_dbg(&plat_dev->dev, "res = 0x%x, reg_base = 0x%lx\n",
 		sp_rtc->res->start, (unsigned long)sp_rtc->reg_base);