RFR: 8351665: Remove unused UseNUMA in os_aix.cpp

[Matthias Baesken]

We have some UseNUMA related coding in os_aix.cpp that is not needed.
UseNUMA is set to false on AIX (with FLAG_SET_ERGO).

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Commit messages:
 - JDK-8351665

Changes: https://git.openjdk.org/jdk/pull/23991/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23991&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8351665
  Stats: 7 lines in 1 file changed: 0 ins; 7 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/23991.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23991/head:pull/23991

PR: https://git.openjdk.org/jdk/pull/23991