[llvm] Update Benchmark (PR #83488)

[Jan Svoboda via llvm-commits]

jansvoboda11 wrote:

My local macOS build is failing after this commit:

```
-- Compiling and running to test HAVE_PTHREAD_AFFINITY
CMake Error at /Users/Jan/Code/upstream-llvm/build/release/CMakeFiles/CMakeTmp/CMakeLists.txt:17 (add_executable):
  Cannot find source file:

    /Users/Jan/Code/upstream-llvm/third-party/benchmark/cmake/pthread_affinity.cpp
```

https://github.com/llvm/llvm-project/pull/83488