[jdk21u-dev] RFR: 8325347: Rename native_thread.h

[Goetz Lindenmaier]

I backport this to make later backports more easy.

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Commit messages:
 - Backport f2f634448e2095f2be1c220d7c10355ab4888439

Changes: https://git.openjdk.org/jdk21u-dev/pull/1761/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1761&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325347
  Stats: 171 lines in 14 files changed: 78 ins; 78 del; 15 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1761.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1761/head:pull/1761

PR: https://git.openjdk.org/jdk21u-dev/pull/1761