[llvm] [llvm-exegesis][AArch64] Disable pauth and ldgm as unsupported instructions (PR #132346)

[David Green via llvm-commits]

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@@ -9,12 +9,54 @@
 #include "AArch64.h"
 #include "AArch64RegisterInfo.h"
 
+#include <linux/prctl.h> // For PR_PAC_* constants
+#include <sys/prctl.h>
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davemgreen wrote:

This might need something like `#ifdef __linux__` to protect it on other systems. 

https://github.com/llvm/llvm-project/pull/132346