[jdk21u] RFR: 8315578: PPC builds are broken after JDK-8304913

[Aleksey Shipilev]

Clean backport to unbreak another build configuration.

Additional testing:
 - [x] macosx-aarch64-server-fastdebug, `jdk/internal/util/ArchTest.java`

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Commit messages:
 - Backport 9559e035d2692d9d61bec2a13b5239a98db077ac

Changes: https://git.openjdk.org/jdk21u/pull/186/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=186&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315578
  Stats: 12 lines in 3 files changed: 12 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u/pull/186.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/186/head:pull/186

PR: https://git.openjdk.org/jdk21u/pull/186