RFR: 8320534: fatal error for the NMTBenchmark test run for the mainline build

[Afshin Zafari]

This benchmark creates and manages threads internally. So, the number of threads is determined by the benchmark and cannot be set in command line arguments.
The number of threads in BenchmarkParams is checked and an exception is thrown if it is invalid.

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Commit messages:
 - 8320534: fatal error for the NMTBenchmark test run for the mainline build

Changes: https://git.openjdk.org/jdk/pull/17824/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17824&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320534
  Stats: 21 lines in 1 file changed: 17 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/17824.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17824/head:pull/17824

PR: https://git.openjdk.org/jdk/pull/17824