[clang] [WinEH] Also check object unwinding for enabling CXXExceptions(/ehs*) (PR #180959)

[Hans Wennborg via cfe-commits]

https://github.com/zmodem approved this pull request.

The change itself LGTM.

I still think "[WinEH] Only emit err_seh_object_unwinding when CXXExceptions are enabled" would be a clearer title.

https://github.com/llvm/llvm-project/pull/180959