Issue #178 Enable FSX checkbox for MSFS on 64-bit

[ajungren]

The FSX checkbox in the config wizard only checked for the fsx plugin, while the checkbox is also used for MSFS. FSX proper isn’t 64-bit so this previously prevented the checkbox to ever be enabled on 64-bit. This PR enables the FSX checkbox if support for either is enabled in the build configuration.

Additionally, the function that checked for MSFS support in the build didn’t actually check for the msfs plugin but rather any of the other plugins using fsxcommon. This PR modifies the logic to check for the msfs plugin itself. I did this in a separate commit so it doesn’t have to be pulled in too if there are any problems with it.

I still need to do some testing to make sure this hasn’t broken anything else, particularly the CBuildConfig change.

[ltoenning]

Thanks for the pull request. Just give me a ping once you have finished your tests, then I will take a look at the changes.

[ajungren]

I tested MSFS on 32- and 64-but and P3D on 64-bit, and made sure the FSX checkbox is enabled if either MSFS or FSX is enabled which I think covers everything. Please do let me know if there's anything I missed, though I don't own FSX proper.

[CLAassistant]

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[ltoenning]

@ajungren Is there any news on this PR?

[ltoenning]

No response for a year. I'll close this for now. @ajungren If you want to continue working on this, feel free to reopen the PR.