[clang] [llvm] [ARM] Add support for Windows SEH (PR #184953)

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kristibektashi wrote:

> This code currently passes all the manual tests that I can throw it with. It is failing quite badly on [Microsoft's Windows SEH tests](https://github.com/microsoft/windows_seh_tests), but when I checked ARM64 `clang`, it also failed with the exact same behavior.

Then perhaps, after this PR is merged, another one could be opened for making these tests pass on both ARM32 and ARM64

https://github.com/llvm/llvm-project/pull/184953