dsound: Avoid using the COM method implementations directly.

[Henri Verbeet]

On 2 September 2016 at 19:17, Andrew Eikum <aeikum at codeweavers.com> wrote:
> I guess I'm not opposed to this, but are these changes useful?
>
It makes the code harder to follow and will generate worse code, if
perhaps both only slightly. That's perhaps not in itself a reason not
to do it, but I do think it makes it harder to justify. I'd be against
this for any code I maintain.