RFR: 8348207: Linux PPC64 PCH build broken after JDK-8347909

[Matthias Baesken]

The Linux PPC64 PCH build was broken after JDK-8347909.

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Commit messages:
 - JDK-8348207

Changes: https://git.openjdk.org/jdk/pull/23268/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23268&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8348207
  Stats: 10 lines in 1 file changed: 0 ins; 2 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/23268.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23268/head:pull/23268

PR: https://git.openjdk.org/jdk/pull/23268