rtc: stop validating rtc_time in .read_time

The RTC core is always calling rtc_valid_tm after the read_time callback.
It is not necessary to call it just before returning from the callback.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-mrst.c

@@ -105,7 +105,7 @@ static int mrst_read_time(struct device *dev, struct rtc_time *time)
 	/* Adjust for the 1972/1900 */
 	time->tm_year += 72;
 	time->tm_mon--;
-	return rtc_valid_tm(time);
+	return 0;
 }
 
 static int mrst_set_time(struct device *dev, struct rtc_time *time)