[llvm] [llvm-exegesis] Use correct rseq struct size (PR #100804)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

@mgorny Can you apply this locally and test that this fixes the issue that you saw? I don't have glibc 2.40 on a machine with perf counters available to test.

https://github.com/llvm/llvm-project/pull/100804