RFR: 8334567: [test] runtime/os/TestTracePageSizes move ppc handling

[Matthias Baesken]

The handling of ppc in runtime/os/TestTracePageSizes should be moved to the test headers.
This is done for x86_64 too in one case, make it more consistent.

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Commit messages:
 - JDK-8334567

Changes: https://git.openjdk.org/jdk/pull/19793/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19793&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8334567
  Stats: 12 lines in 1 file changed: 5 ins; 6 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19793.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19793/head:pull/19793

PR: https://git.openjdk.org/jdk/pull/19793