Please merge this patch for the PA driver in SDL.

http://0pointer.de/public/sdl-pulse-rework.patch

This patch:
- fixes buffering (i.e. reduces number of "fragments" to 2, doesn't defer
filling up of the buffer until the entire buffer ran completely empty.)
- drops $PASERVER and $PADEVICE env var support, since this is a duplication of
$PULSE_SERVER and $PULSE_SINK which the PA libs honor anyway.

This fixes the sound issues in all games I tested.

--HG--
branch : SDL-1.2
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%403846