audio: Centralize audio configuration paths specification

The list of possible paths for the audio configuration
files is now retrieved using audio_get_configuration_paths()
function. All duplicated lists of known configuration
directories have been removed.

Bug: 153680356
Test: atest VtsHalAudioV6_0TargetTest \
            VtsHalAudioPolicyV1_0TargetTest \
            VtsHalAudioEffectV6_0TargetTest
Change-Id: I1e40fdf8d6e3a5ac339f7f138f62063bb87bd3da
Merged-In: I1e40fdf8d6e3a5ac339f7f138f62063bb87bd3da