RFR: 8333264: Remove unused resolve_sub_helper declaration after JDK-8322630

[Tobias Hartmann]

The `resolve_sub_helper` declaration is unused. Noticed this when working on the Valhalla merge.

Thanks,
Tobias

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Commit messages:
 - 8333264: Remove unused resolve_sub_helper declaration after JDK-8322630

Changes: https://git.openjdk.org/jdk/pull/19476/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19476&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333264
  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19476.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19476/head:pull/19476

PR: https://git.openjdk.org/jdk/pull/19476