NuPlayer: use acquireWakeLockAsync in AWakeLock

It appears the IPowerManager::acquireWakeLock() does not transport the
Display ID properly causing a failure to acquire a wakelock from native
code.
Use acquireWakeLockAsync until the problem is root caused.

Bug: 234429395
Test: repro steps in bug
Change-Id: Ice44a818c8c18e42008eb5271d37d263fee57484
1 file changed