AudioTrack: 24 channel index masks, compressed formats

PCM channel count is limited to AudioSystem.CHANNEL_OUT_MAX.

Compressed channel count is limited to AudioSystem.FCC_24
as typically the data rate is smaller than the equivalent
PCM channel count stream.

Test: atest AudioTrackTest
Test: atest AudioTrackTest#testImmersiveStreaming
Test: atest AudioTrackTest#testImmersiveChannelIndex
Bug: 187062102
Change-Id: I96b2e37c9b59c9e38a0caf69e19c280949c4d099