Use timeout for *dexopt* wake lock

There are reports of *dexopt* lock being held for 10+ minutes, which shouldn't
normally happen on threads that are monitored by the Watchdog. Added
logging to help detecting that.

The lock is now held with a timeout of WAKELOCK_TIMEOUT_MS. It is set to a
higher value than PM's watchdog timeout for easier reading from a timing
histogram.

Test: Manual, device boots without errors
Bug: 37756892
Change-Id: Iac569474d1c95447e08fe5e9870e4518b8d22c65