flacdec: use init_get_bits8()

Signed-off-by: Paul B Mahol <onemda@gmail.com>
tta: return meaningful error codrs

Signed-off-by: Paul B Mahol <onemda@gmail.com>
tta: add support for reading ape tags

Signed-off-by: Paul B Mahol <onemda@gmail.com>
lavf/aacdec: add support for reading ape tags

Closes #2634.

Signed-off-by: Paul B Mahol <onemda@gmail.com>
vc1dec: Disable dead code

Fixes CID732197/6

A assert is added to check that the disabled code wont
be needed in the future.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>