ole32: fix offsets managment

[Dan Kegel]

f.dorin at free.fr wrote:
> It's my first patch. So, if something is wrong, don't hesitate to notify me !
> ...
> +  if (*(const WORD*)pFormat) pointer_desc = pFormat + *(const SHORT*)pFormat;

Hi François!
A few quick notes:
1) it's helpful if you can say what app each patch fixes, and what the
symptom was
2) it's very helpful if you can include a conformance test with each patch.
It can probably be just a few lines added to an existing conformance test.
3) In this patch, it looks kind of funny to use WORD and SHORT for same type,
may as well change the type in the conditional, too.
- Dan