[clang] [AArch64][PAC][clang][ELF] Support PAuth ABI compatibility tag (PR #85235)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,32 @@
+// Check that we can manually enable specific ptrauth features.
+
+// RUN: %clang -target aarch64 -c %s -### 2>&1 | FileCheck %s --check-prefix NONE
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MaskRay wrote:

`--target=` for new tests

https://github.com/llvm/llvm-project/pull/85235