Spatializer: Cumulative headtracking fixes

Add thread name for proper debugging.
Raise headtracking event thread priority from normal to highest non-realtime.
Raise spatializer looper thread priority from audio to highest non-realtime.
Prevent logspam on error.
Add sensor start / stop logging.

Test: Validate HT works
Bug: 258737281
Merged-In: Idd80929c43a06eaf6480b569384245b8f66f806f
Change-Id: Idd80929c43a06eaf6480b569384245b8f66f806f
diff --git a/services/audiopolicy/service/Spatializer.cpp b/services/audiopolicy/service/Spatializer.cpp
index ad76202..277c91b 100644
--- a/services/audiopolicy/service/Spatializer.cpp
+++ b/services/audiopolicy/service/Spatializer.cpp
@@ -263,7 +263,7 @@
     mLooper->start(
             /*runOnCallingThread*/false,
             /*canCallJava*/       false,
-            PRIORITY_AUDIO);
+            PRIORITY_URGENT_AUDIO);
 
     mHandler = new EngineCallbackHandler(this);
     mLooper->registerHandler(mHandler);