[libunwind] [libunwind] Fix building with EXCEPTION_DISPOSITION as enum (PR #180513)

[Jacek Caban via cfe-commits]

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@@ -266,7 +266,7 @@ __libunwind_seh_personality(int version, _Unwind_Action state,
   _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() LanguageHandler "
                              "returned %d",
                              (int)ms_act);
-  switch (ms_act) {
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cjacek wrote:

Looks reasonable to me, with one nitpick: we're now casting `ms_act` on every use, maybe we should just change its type instead.

https://github.com/llvm/llvm-project/pull/180513