rtc: fix the error in the function of cmos_set_alarm

There is a bug in the function of cmos_set_alarm.  RTC alarm time for October
can't be set correctly.

For October: 0x0A will be written into the RTC region (MONTH_ALARM) in current
kernel.  But in fact 0x10 should be written.  Wildcards are also not handled
correctly.
Signed-off-by: NZhao Yakui <yakui.zhao@intel.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-cmos.c

@@ -198,9 +198,8 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 
 	/* Writing 0xff means "don't care" or "match all".  */
 
-	mon = t->time.tm_mon;
-	mon = (mon < 12) ? BIN2BCD(mon) : 0xff;
-	mon++;
+	mon = t->time.tm_mon + 1;
+	mon = (mon <= 12) ? BIN2BCD(mon) : 0xff;
 
 	mday = t->time.tm_mday;
 	mday = (mday >= 1 && mday <= 31) ? BIN2BCD(mday) : 0xff;