dsound: Disable property sets if hardware doesn't support it

[Robert Reif]

This patch: 
http://www.winehq.org/pipermail/wine-patches/2007-June/039942.html
causes RightMark3DSound.exe 
(http://audio.rightmark.org/products/rm3ds.shtml) to crash.

It appears that the code always expects a property set interface to 
succeed and
crashes on a NULL pointer when it doesn't.

Reverting this patch lets the program run.