[jdk16] RFR: 8258094: AIX build fails after 8257602

[Markus Grönlund]

Greetings,

AIX/xlc does not support the THREAD_LOCAL macro.

This changes moves more involved event posting from gc/shared into JFR.

Thanks
Markus

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Commit messages:
 - whitespace
 - move more involved event posting to jfr

Changes: https://git.openjdk.java.net/jdk16/pull/11/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16&pr=11&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8258094
  Stats: 239 lines in 5 files changed: 156 ins; 79 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk16/pull/11.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16 pull/11/head:pull/11

PR: https://git.openjdk.java.net/jdk16/pull/11