Spatializer: Tuning for least squares prediction

Made the prediction verifier more extensible for testing.

Allow audio.spatializer.prediction_duration_ms == 0
for testing.

Test: adb shell dumpsys media.audio_policy
Bug: 274847421
Merged-In: I1ffd9510a29bcca6c043c7e282f7d1fa1e3ed4ce
Change-Id: I1ffd9510a29bcca6c043c7e282f7d1fa1e3ed4ce