src/mixer.c: Fix a debug typo and some return stuff that was causing  compiler warnings.
src/mixer.c: Fix a debug typo and some return stuff that was causing 
compiler warnings.

Note that mixer_main_thread() generates a warning about a non-void 
function, but it appears to be void to me.  Go figure.

Also, mixer_stop() has a comment about the stopping process possibly 
being completely broken.  Threads are far beyond my abilities, so 
someone should probably take a look at this.


git-svn-id: 5a113f46df058f8047e288f4f3e948d899353d9a@431 410355f2-c4ea-45de-a5b5-301721f902b9

mwcampbell/prs,mwcampbell/prs,mwcampbell/prs