Allow trout targets to switch audio hal implementation

Trout can run on both Cuttlefish and Emulator audio HAL implementations
This CL allows switching those HALs by toggling a single build-time
switch: TARGET_USES_CUTTLEFISH_AUDIO

Bug: 166306608
Bug: 163092759
Test: build with cuttlefish audio, test that sound works
Change-Id: I294b1787281aa85aab98b63f961da5f0410fd53c
3 files changed