Make win32.mak compatible with MODEL=32omf

[MoonlightSentinel]

The previous assumption was MODEL=32 because MODEL=32mscoff is built by win64.mak.

Verified locally because Azure requires further changes outside of this repository.

[dlang-bot]

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Bugzilla references

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If your PR contains non-trivial changes, please reference a Bugzilla issue or create a manual changelog.

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + druntime#3703"

[MoonlightSentinel]

This will need to be force-merged because it requires additional changes to dmd/windows.sh and phobos/win32.mak

[RazvanN7]

@MoonlightSentinel Ping me when you need this merged.

[MoonlightSentinel]

Submitted the required changes to windows.sh here: dlang/dmd#13572. That should enable Azure to build Druntime with MODEL=32omf again (but still fail on Phobos - will open another PR for that).

[MoonlightSentinel]

Azure successfully built druntime! Just one patch left... (Phobos/win32.mak)

[MoonlightSentinel]

Can you temporarily mark the Azure job as not required? Or do we have to modify the configuration until the Phobos PR is merged?

[RazvanN7]

I don't know how to do that and I might not have the rights, however, I can force merge this if that is required.

[MoonlightSentinel]

It'll be required - neither makefile update is sufficient on its own (this fails due to the outdated phobos/win32.mak and a Phobos PR cannot build Druntime without this patch)

[RazvanN7]

@MoonlightSentinel Thanks for fixing this!