Use audio_format_t consistently

Was int, uint32_t, uint16_t, and uint8_t with 2-bit bitfield.
Also replace 0 by AUDIO_FORMAT_DEFAULT and replace 1 by
AUDIO_FORMAT_PCM_16_BIT.

Change-Id: Ia8804f53f1725669e368857d5bb2044917e17975
diff --git a/media/libmedia/JetPlayer.cpp b/media/libmedia/JetPlayer.cpp
index afa84b7..25c4898 100644
--- a/media/libmedia/JetPlayer.cpp
+++ b/media/libmedia/JetPlayer.cpp
@@ -91,7 +91,7 @@
     mAudioTrack = new AudioTrack();
     mAudioTrack->set(AUDIO_STREAM_MUSIC,  //TODO parametrize this
             pLibConfig->sampleRate,
-            1, // format = PCM 16bits per sample,
+            AUDIO_FORMAT_PCM_16_BIT,
             (pLibConfig->numChannels == 2) ? AUDIO_CHANNEL_OUT_STEREO : AUDIO_CHANNEL_OUT_MONO,
             mTrackBufferSize,
             0);