RFR: 8340436: Remove unused CompressedOops::AnyNarrowOopMode

[Kim Barrett]

Please review this trivial change to remove an unused enumerator.

Testing: mach5 tier1

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Commit messages:
 - remove unused AnyNarrowOopMode

Changes: https://git.openjdk.org/jdk/pull/21098/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21098&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8340436
  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21098.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21098/head:pull/21098

PR: https://git.openjdk.org/jdk/pull/21098