audio: derive sound device for concurrent playback usecases am: 2d809e0d10 am: 8a692c65cc
am: 63bbcbc7e5

Change-Id: Ib8fc1761e38f1206c17f85fbf96613907486e608
tree: 1be1eeb67a536c3b29047d5867a14d69c9942e17
  1. hal/
  2. legacy/
  3. post_proc/
  4. visualizer/
  5. voice_processing/
  6. Android.mk