rtc: pcf85063: remove RTC_VL_CLR handling

Remove RTC_VL_CLR handling because it is a disservice to userspace as it
removes the important information that the RTC data is invalid. This may
lead userspace to set an invalid system time later on.

Link: https://lore.kernel.org/r/20191214220259.621996-11-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-pcf85063.c

@@ -299,12 +299,6 @@ static int pcf85063_ioctl(struct device *dev, unsigned int cmd,
 
 		return 0;
 
-	case RTC_VL_CLR:
-		ret = regmap_update_bits(pcf85063->regmap, PCF85063_REG_SC,
-					 PCF85063_REG_SC_OS, 0);
-
-		return ret;
-
 	default:
 		return -ENOIOCTLCMD;
 	}