This is never mentioned in the specifications, and decoders work
just as fine without it. Update the fate references since the compressed
file is smaller.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Each fate-seek test depends now only on the corresponding fate-acodec,
fate-vsynth2 or fate-lavf test which creates the file seek-tests
operates on. The tests and references are renamed to match the test they
depend on.
