[jdk17u-dev] RFR: 8317960: [17u] Excessive CPU usage on AbstractQueuedSynchronized.isEnqueued

[David Alvarez]

This patch brings the AbstractQueuedSynchronizer related changes from [JDK-8277090](https://bugs.openjdk.org/browse/JDK-8277090) to fix a performance issue that can happen in JDK17 too.

The rest of JDK-8277090 are done mostly in preparation of virtual threads and are covered under CSR [JDK-8285450](https://bugs.openjdk.org/browse/JDK-8285450). There is no plan at the moment to backport the rest of the changes to 17.

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Commit messages:
 - 8317960: [17u] Excessive CPU usage on AbstractQueuedSynchronized.isEnqueued

Changes: https://git.openjdk.org/jdk17u-dev/pull/1875/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1875&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317960
  Stats: 6 lines in 2 files changed: 4 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1875.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1875/head:pull/1875

PR: https://git.openjdk.org/jdk17u-dev/pull/1875