[jdk25u] RFR: 8358340: Support CDS heap archive with Generational Shenandoah

[Aleksey Shipilev]

Enables AOT/CDS caches with Generational Shenandoah.

Additional testing:
 - [x] Linux x86_64 server fastdebug, `runtime/cds` with Generational Shenandoah

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Commit messages:
 - Backport 577ac0610a0c62d6a3f5501bb0d1bd45f8c47f22

Changes: https://git.openjdk.org/jdk25u/pull/248/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u&pr=248&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8358340
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk25u/pull/248.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u.git pull/248/head:pull/248

PR: https://git.openjdk.org/jdk25u/pull/248