[cxx-interop][5.9] windows ABI fixes

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[cxx-interop] Fix the windows ABI for returning indirect values out of methods

Fixes https://github.com/apple/swift/issues/66326

This allows us to reneable Windows method tests. Note that Windows still has
a broken convention for non-trivial record with non-trivial destructor but
trivial copy-constructor, so classes in the methods.swift test need an explicit
copy constructor.

Fixes rdar://88391102

[cxx-interop] Windows: unify address-only logic and mark non-trivial loadable C++ types as unavailable

Windows logic for determining address-only type layout for a C++ type is now unified with other platforms.
However, this means that on Windows, a C++ type with a custom destructor, but a default copy constructor
is now loadable, even though it's non-trivial. Since Swift does not support such type operations at the
moment (it can't be yet destroyed), mark such type as unavailable in Swift instead, when building for
the Windows target.

This fixes the Windows miscompilation related to such types when they were passed indirectly to C++
functions even though they're actually passed directly.

• Explanation:
  Windows MSVC ABI had two problems with IRGen for calls to C++:

1. Methods returning values indirectly had incorrect order between this and the returned value. This is now fixed, and we get the ordering right for the MSVC ABI.
2. Non-trivial but passed in registers types (MSVC ABI example - C++ class with destructor but default copy constructor) were incorrectly passed indirectly as we marked them as address-only. This patch now marks them loadable, which fixes that issue. However, we cannot yet support such types correctly semantically, as they can't be yet destroyed from Swift. Therefore, mark such types as unavailable on Windows to avoid missing C++ destructor calls from Swift.

• Scope: C++ interop, Clang importer, IRGen.
• Risk: Low, the affected code changes only affect the MSVC windows target, and only affect C++ imported types, not C.
• Testing: Unit tests.
• Original PR: [cxx-interop] windows methods fixes #67268

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@swift-ci please test

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@swift-ci please test windows platform

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@swift-ci please test linux platform

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@swift-ci please test

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@swift-ci please test source compatibility