[lld] [LLD][ELF][AArch64] Add BTI Aware long branch thunks (PR #108989)

[Fangrui Song via llvm-commits]

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@@ -200,6 +203,14 @@ class ThunkCreator {
   // The Mips LA25 Thunk is an example of an inline ThunkSection.
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MaskRay wrote:

Perhaps update this comment to mention `AArch64BTILandingPadThunk`

https://github.com/llvm/llvm-project/pull/108989