Log Message:
SDL: sync options with SDL2

as discussed at pkgsrccon, this was pretty much the only thing still using
or supporting esound. the esound website doesn't even exist any more. NAS
might still be useful, but maybe only if you're using IRIX or something

i'm especially worried about libaudiofile and spidermonkey52 being pulled
in by esound and pulseaudio respectively - the maintainance status of these
libraries is very unclear and their security record is quite problematic.

also:
- Linux gets ALSA.
- explicitly disable support for PlayStation video outputs
  if you get pkgsrc to work on the PlayStation OS please submit a talk
- add pkg-config to USE_TOOLS, it seems to be used in some circumstances.