This fixes an crash caused by using the type from
FlacSubframeHeader::order (unsigned 8-bit), which after overflowing
the integer, converting it back to u32, and decrementing by one
resulted in accessing an array waaay out of bounds.
This commit adds a loader for the FLAC audio codec, the Free Lossless
Audio codec by the Xiph.Org foundation. LibAudio will automatically
read and parse FLAC files, so users do not need to adjust.
This implementation is bare-bones and needs to be improved upon.
There are many bugs, verbatim subframes and any kind of seeking is
not supported. However, stereo files exported by libavcodec on
highest compression setting seem to work well.
