codecs.conf: add libavcodec h264_vda (OSX Video Decode Acceleration)
Add a codecs.conf entry to enable specifying the libavcodec h264_vda
decoder. Currently this decoder exists in libavcodec from FFmpeg only,
not Libav.
Video Decode Acceleration Framework is a framework by Apple to provide
GPU assisted H.264 decoding. It is available on Mac OS X v10.6.3 and
later with Mac models equipped with the NVIDIA GeForce 9400M, GeForce
320M, GeForce GT 330M, ATI HD Radeon GFX, Intel HD Graphics and
others.