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

[David Green via llvm-commits]

https://github.com/davemgreen commented:

Thanks - looking good. You might need to limit the test to linux too, if it isn't expected to be able to run or give the same output on osx/windows.

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