rtc: simplify implementations of read_alarm

Since commit d68778b80d ("rtc: initialize output parameter for read
alarm to "uninitialized"") there is no need to explicitly set
unsupported members to -1. So drop the respective assignments from
drivers.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

drivers/rtc/rtc-hym8563.c

@@ -213,9 +213,6 @@ static int hym8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 					-1 :
 					bcd2bin(buf[3] & HYM8563_WEEKDAY_MASK);
 
-	alm_tm->tm_mon = -1;
-	alm_tm->tm_year = -1;
-
 	ret = i2c_smbus_read_byte_data(client, HYM8563_CTL2);
 	if (ret < 0)
 		return ret;