CPUIDLE: Avoid remnant LAPIC timer intr while force hpetbroadcast

CPUIDLE: Avoid remnant LAPIC timer intr while force hpetbroadcast

LAPIC will stop during C3, and resume to work after exit from
C3. Considering below case:
The LAPIC timer was programmed to expire after 1000us, but CPU enter
C3 after 100us and exit C3 at 9xxus.

   0us: reprogram_timer(1000us)
 100us: entry C3, LAPIC timer stop
 9xxus: exit C3 due to unexpected event, LAPIC timer continue running
10xxus: reprogram_timer(1000us), fail due to the past expiring time.
......: no timer softirq raised, no change to LAPIC timer.
......: if entry C3 again, HPET will be forced reprogramed to
 now+small_slop.
......: if entry C2, no change to LAPIC.
18xxus: LAPIC timer expires unexpectedly if no C3 entries after
 10xxus.

Signed-off-by: Wei Gang <gang.wei@intel.com>