audio spatializer: monitor screen sensor only when needed

Only monitor the screen sensor when the head sensor must also
be monitored:
    - spatialization is enabled
    - head tracking is requested
    - a head pose sensor is registered
    - tracks are active on the spatializer output

Also remove excessive verbose log.

Bug: 224623509
Test: boot and check sensors
Change-Id: Icf0e4f69d3d342048decb127c23bf79ff196b8d4
diff --git a/services/audiopolicy/service/Spatializer.h b/services/audiopolicy/service/Spatializer.h
index 4ce99d8..1382124 100644
--- a/services/audiopolicy/service/Spatializer.h
+++ b/services/audiopolicy/service/Spatializer.h
@@ -276,7 +276,12 @@
 
     void postFramesProcessedMsg(int frames);
 
-    void checkHeadSensor_l() REQUIRES(mLock);
+    /**
+     * Checks if head and screen sensors must be actively monitored based on
+     * spatializer state and playback activity and configures the pose controller
+     * accordingly.
+     */
+    void checkSensorsState_l() REQUIRES(mLock);
 
     /** Effect engine descriptor */
     const effect_descriptor_t mEngineDescriptor;