Fix various function prototypes

[Dmitry Timoshkov]

"Vincent Béron" <vberon at mecano.gme.usherb.ca> wrote:

> SHCoCreateInstance returns void, not HRESULT.

According to Platform SDK headers SHCoCreateInstance returns HRESULT.

P.S.
Do you compile Wine with _WIN64 defined on Alpha? That would be really
cool to see that going, clean our headers and fix all warnings caused
by 32 bit pointer assumptions.

--
Dmitry.