[llvm] [llvm-exegesis] Add support for pinning benchmarking process to a CPU (PR #85168)

[Clement Courbet via llvm-commits]

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@@ -418,8 +423,15 @@ static void runBenchmarkConfigurations(
         std::optional<StringRef> DumpFile;
         if (DumpObjectToDisk.getNumOccurrences())
           DumpFile = DumpObjectToDisk;
+        std::optional<int> BenchmarkCPU = std::nullopt;
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legrosbuffle wrote:

After the suggestion above, this can be:
`const std::optional<int> BenchmarkCPU = BenchmarkProcessCPU != -1 ? std::nullopt : std::make_optional(BenchmarkProcessCPU);`


https://github.com/llvm/llvm-project/pull/85168