audiolfinger: implement latency mode control in spatializer mixer

Add audio HAL stream latency mode control logic to
Spatialier mixer thread:
- Query supported latency modes from HAL stream and register mode
change callback: when mode changes either from callback or routing
change, notify Spatializer effect client via IAudioFlingerClient
interface.
- Compute requested latency mode based on the requested mode and
active spatialized tracks and request it from HAL stream.

Bug: 218273231
Test: make
Merged-In: Ifc4445e1ce554631dbcffaf478fbe8a33ec1b5ab
Change-Id: Ifc4445e1ce554631dbcffaf478fbe8a33ec1b5ab