[clang] [clang] Add arm64e ABI-defined key assignments to ptrauth.h. (PR #93901)

[Anton Korobeynikov via cfe-commits]

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@@ -15,6 +15,29 @@ typedef enum {
   ptrauth_key_asib = 1,
   ptrauth_key_asda = 2,
   ptrauth_key_asdb = 3,
+
+#ifdef __APPLE__
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asl wrote:

I believe these are defaults for ELF as well. So, I'd remove ifdef and decide on necessary gating when there will be a precedent.

https://github.com/llvm/llvm-project/pull/93901