Revert "audio: Only allow legacy HAL"

This reverts commit 949e8ddbcfe6f6663ae5f41ae4cde413592c469b.

Change-Id: I752e9976ddf16ec53b4179194b42412f8bcf5f87
alsa_sound: Add support for "Voice Earpiece Extra Gain" mode

Uses "Voice Earpiece Extra Gain" mode instead of "Voice Earpiece" during
voice calls when persist.audio.voc_ep.xgain=1.

Change-Id: I9f00a81687fa9605c68308a74e0ffaaea7e698fc
hal: Use correct path for audio_defs header

Change-Id: I10f0e842e2ffb9ed9a67a2f62f93bd47cb2f28ad
audio: Make CAF audio HALS platform specific

Change-Id: Ie4d7a1a872c41269a280271bcd4cb14ee37cd050