[clang] [clang][PAC][darwin] Set correct default ptrauth features for arm64e-darwin (PR #153722)

[Ahmed Bougacha via cfe-commits]

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+// RUN: %clang -target arm64                   -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64-apple-macosx      -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64-darwin            -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64-apple-darwin      -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64-apple-ios-macabi  -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64-linux-gnu         -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
+// RUN: %clang -target arm64e-linux-gnu        -DNO_DEFAULT_PTRAUTH     %s -fsyntax-only -Xclang -verify=no_default_ptrauth
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ahmedbougacha wrote:

I'd leave it to them to add this if needed, but in general I don't think any other target really has as much emphasis on platform defaults as we can afford for darwin;  in this case I believe it's all gated by the pauthabi machinery and whatnot, which is thoroughly tested elsewhere

https://github.com/llvm/llvm-project/pull/153722