Merge commit 'c9a13a28'

* commit 'c9a13a28':
  lavc: remove old unused audio conversion functions.

Conflicts:
	libavcodec/audioconvert.c
	libavcodec/audioconvert.h

Merge only for metadata.
keeping the old API longer reduces the need for applications to be continuously
updated.
Merged-by: Michael Niedermayer <michaelni@gmx.at>