audioflinger: remove wake lock implementation from APS

-AudioPolicyService is not able to acquire the wakelock.
 None of the Audio functionality is impacted though it always fails
 to hold the wakelock.

-APS tries to access wake lock directly using hardware_legacy APIs
 and it always fails due to lack of capability.

-Remove the wake lock implementation since it always fails and
 it does not impact any audio functionality.

Change-Id: I0055c188fb8d6fd70a27c3945f5e68addac8509b