[vlc-devel] Fix #8124 (planar audio in 2.0) try 3

[Rafaël Carré]

Now with:
- encoder changes
- check if libavcodec supports planar formats

 configure.ac                    |    7 +++++--
 modules/codec/avcodec/audio.c   |   68 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------
 modules/codec/avcodec/avcodec.h |    9 +++++++++
 modules/codec/avcodec/encoder.c |   65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++------
 4 files changed, 135 insertions(+), 14 deletions(-)