Due to a shortcoming in the AAC specification, if an all zero buffer is
fed to section data decoding it will never terminate. That means without
a buffer exhaustion check decode_band_types() will consume all input
buffer padding. Worse if a get_bits() implementation that returns zeros
when padding is exhausted is used, the function will never terminate.

The fixes that by added a buffer exhaustion check in the sectioning
decoding loop.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@22044 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b