[clang] [clang] Function type attribute to prevent CFI instrumentation (PR #135836)

[Erich Keane via cfe-commits]

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@@ -5250,6 +5260,7 @@ class FunctionProtoType final
     FunctionType::ExtInfo ExtInfo;
     unsigned Variadic : 1;
     unsigned HasTrailingReturn : 1;
+    unsigned CFIUncheckedCallee : 1;
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erichkeane wrote:

I realize this type isn't doing this, but I think we want a:
`LLVM_PREFERRED_TYPE(bool)`
before this. (and probably the two above).

https://github.com/llvm/llvm-project/pull/135836