[lld] [lld][AArch64][ELF][PAC] Support AUTH relocations and AUTH ELF marking (PR #72714)

[Fangrui Song via llvm-commits]

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@@ -2619,6 +2623,42 @@ static uint32_t getAndFeatures() {
   return ret;
 }
 
+static void getAArch64PauthInfo() {
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MaskRay wrote:

I think `uint32_t getAndFeatures` can be renamed to `void readSecurityNotes`. `readSecurityNotes` sets `andFeatures` internally, and  `getAArch64PauthInfo` is merged into it.

This way we iterate objectFiles just once for aarch64.

https://github.com/llvm/llvm-project/pull/72714