[MSI/tests] ConvertSidToStringSid not available on win98/NT4

[Juan Lang]

> Thats not exactly what I meant, I think. This Kerberos support comes
> from extra functions
> in secur32.dll right? The tests then will notice that there is no
> Kerberos support and not
> run Kerberos tests. Am I mistaken?

You are mistaken.  The same functions exist in Windows NT4 (they're in
security.dll rather than secur32.dll, but the exports are the same.)
You ask for a provider by name, and the Kerberos provider exists in
Windows 2000 and up, but not in NT4.

That doesn't mean that the tests couldn't use skip if Kerberos isn't available.
--Juan