SDL_sound + MIDI on MacOS X.

[Ryan C. Gordon]

The latest CVS of SDL_sound fixes MIDI decoding for bigendian platforms
like MacOS X. If it was giving you problems, please sync up to the latest.

SDL_mixer didn't have this particular bug, but seems to have other
byteswapping bugs that prevent it from loading a MIDI file in the first
place. If someone wants to diff the two codebases (SDL_sound's MIDI
decoder is based on SDL_mixer's from way back) and figure out why, I'll
get the SDL_mixer patch into CVS.

--ryan.