AE: accept planar formats and pts from player

ActiveAE now supports planar audio formats at input. Decoded planar audio from .i.e. dts or dd can go all the way through AE to the sink. In particular interesting for Pi , @popcornmix

Simplify dvdplayer's interface to AE. Drop obsolete conversion to interleaved in ffmpeg audio codec. Pass pts to AE instead of guessing playing pts by error prone calculation using delay.
Drop obsolete leftover buffer, we only get entire frames from the codecs.

Drop obsolete pcm audio codecs. lpcm wasn't used anyway. Nothing which can't be done by ffmpeg.

Adjust paplayer to interface changes.

@elupus I have based this on masterclock for testing. 
yea, pcm_dvd is the LPCM one. I fully agree that LPCM is a misnomer, it's just what it was called on DVD when it showed up. The point was that the decoder can easily skip the higher than 16bits of each sample by just setting a sample stride (same as linesize/stride on video) and output to a 16bit capable stereo without much overhead.

Fully possible this code have been dead for quite some time.