Alarm: Use dedicated alarm type for poweroff alarm.

RTC_POWEROFF_WAKEUP is a new alarm type introduced by framework
to perform poweroff alarm. The time (RTC_WAKEUP) set to framework
is not the same as the alarm time set in deskclock.  In this case
the RTC register might not be correctly set. So both RTC_WAKEUP
and RTC_POWEROFF_WAKEUP types need to be set at the same time:
RTC_WAKEUP type will handle the normal alarm process, and
RTC_POWEROFF_WAKEUP is used to set the correct alarm time to RTC
register.

Change-Id: Ic03f87018e163adf6f6e6013963a497d340fbec7
Remove LOCAL_SDK_VERSION definition to use hidden API

Remove LOCAL_SDK_VERSION definition to use the hidden alarm type
RTC_POWEROFF_WAKEUP in DeskClock.

Change-Id: I3e3ebc2a1be75eddf6980915b598d2a9523dfd61
DeskClock: Fix the delay or missed condition of the alarm after boot

After boot completed, if low memory condition happens or some ordered
broadcasts have time out It will cause some delay to some other ordered
broadcasts like "change_state" broadcast for alarm. Because alarm is
very sensitive to the time, its broadcast should be changed into one
with high priority. And the priority of AlarmInitReceiver should be
impoved to receive the BOOT_COMPLETE action in time. Otherwise the
alarm will be missed if AlarmInitReceiver receive the action after
the alarm time.

CRs-Fixed: 621073
Change-Id: I18f37378e5eef0504c9c412d3a2ff85487093245