RFR: 8300295: [AIX] TestDaemonDestroy fails due to !is_primordial_thread assertion [v2]

[Varada M]

> The assertion failure with exit value 134 for the test TestDaemonDestroy.java is because when the JNI_CreateJavaVM is being called by main thread on AIX it prevents the jvm creation on the primordial thread on AIX. This is solved in such a way that when JNI_CreateJavaVM is called it runs in pthread thus enabling the creation of jvm. 
> 
> JBS issue for this test : [JDK-8300295](https://bugs.openjdk.org/browse/JDK-8300295)

Varada M has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - 8300295: [AIX] TestDaemonDestroy fails due to !is_primordial_thread assertion
 - 8300295: [AIX] TestDaemonDestroy fails due to !is_primordial_thread assertion

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Changes:
  - all: https://git.openjdk.org/jdk/pull/12006/files
  - new: https://git.openjdk.org/jdk/pull/12006/files/75255899..ddde3f00

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12006&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12006&range=00-01

  Stats: 16314 lines in 710 files changed: 5664 ins; 3974 del; 6676 mod
  Patch: https://git.openjdk.org/jdk/pull/12006.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12006/head:pull/12006

PR: https://git.openjdk.org/jdk/pull/12006