[jdk21u-dev] RFR: 8317801: java/net/Socket/asyncClose/Race.java fails intermittently (aix)

[Shruthi Acharya]

This pull request contains a backport of commit [8f121a17](https://github.com/openjdk/jdk/commit/8f121a173ca2534c706682f6c68fbbb0b94ec057) from the [openjdk/jdk](https://git.openjdk.org/jdk) repository.
OpenJDK bug : https://bugs.openjdk.org/browse/JDK-8317801

The original patch didn’t apply cleanly to the JDK21u-dev branch due to a copyright header mismatch in `src/java.base/unix/classes/sun/nio/ch/NativeThread.java`. However, the rest of the changes were ported without issues. Manually updated the copyright header to resolve the conflict.

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Commit messages:
 - Backport 8f121a173ca2534c706682f6c68fbbb0b94ec057

Changes: https://git.openjdk.org/jdk21u-dev/pull/2543/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2543&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317801
  Stats: 39 lines in 4 files changed: 32 ins; 4 del; 3 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2543.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2543/head:pull/2543

PR: https://git.openjdk.org/jdk21u-dev/pull/2543