[jdk21u-dev] RFR: 8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers

[Jan Kratochvil]

A patch 4 of 6 for: [[21u] Backport intention of 8322420: [Linux] cgroup v2: Limits in parent nested control groups are not detected](https://mail.openjdk.org/pipermail/jdk-updates-dev/2025-April/043206.html)

It has a patch dependency on PR 3 of 6: https://github.com/openjdk/jdk21u-dev/pull/1661

This backport is clean.

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Depends on: https://git.openjdk.org/jdk21u-dev/pull/1661

Commit messages:
 - 8331560: Refactor Hotspot container detection code so that subsystem delegates to controllers

Changes: https://git.openjdk.org/jdk21u-dev/pull/1662/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1662&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331560
  Stats: 543 lines in 8 files changed: 315 ins; 79 del; 149 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1662.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1662/head:pull/1662

PR: https://git.openjdk.org/jdk21u-dev/pull/1662