tegra3-common: Update media_codecs, media_profiles and audio_policy

* Include google and ffmpeg codecs
* Remove camera 2 and 3 from media_profiles
  Our device only has two cameras
* Add r_submix and usb audio modules to audio_policy
  Possible future Chromecast and USB audio support

Change-Id: I01f40813f2adf8097e3f79c7621f99b3d96a170a