AudioFlinger: Boost priority on a separate thread

Ensures no contention between priority boost
and audio patch configuration, since priority boost
requires waiting for the SchedulingPolicyService
to be available which may increase boot time.

Test: Spatializer continues to work
Bug: 297322674
Change-Id: Ieed64fbff98eecb6e039f3afd1b661514a227334
1 file changed