[jdk22u] RFR: 8327210: AIX: Delete obsolete parameter Use64KPagesThreshold

[Joachim Kern]

As the configuration parameter Use64KPagesThreshold on AIX is not needed anymore, we remove it from the code.

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Commit messages:
 - Backport 0ae4fa71e425316a695cfd7e14835effd0cf23b9

Changes: https://git.openjdk.org/jdk22u/pull/100/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk22u&pr=100&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8327210
  Stats: 19 lines in 3 files changed: 0 ins; 14 del; 5 mod
  Patch: https://git.openjdk.org/jdk22u/pull/100.diff
  Fetch: git fetch https://git.openjdk.org/jdk22u.git pull/100/head:pull/100

PR: https://git.openjdk.org/jdk22u/pull/100