[8/8] msi: Avoid Wow6432Node usage in registry table handling.

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
https://testbot.winehq.org/JobDetails.pl?Key=8000

Your paranoid android.


=== w2000pro (32 bit install) ===
The test timed out

=== wxppro (32 bit install) ===
The test timed out