RFR: 8331771: ZGC: Remove OopMapCacheAlloc_lock ordering workaround

[Aleksey Shipilev]

After [JDK-8331714](https://bugs.openjdk.org/browse/JDK-8331714), we don't need the Generational Z kludge that works around the lock ranking problem with (now gone) `OopMapCacheAlloc_lock`. I also reverted the `DisableIs*Mark` that was added specifically for that kludge in JDK 21. This simplifies further additions of new marks that do not have to replicate `Disable*` code.

Additional testing:
 - [ ] Linux x86_64 server fastdebug, `hotspot_gc`

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Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/19114/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19114&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331771
  Stats: 22 lines in 4 files changed: 0 ins; 22 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19114.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19114/head:pull/19114

PR: https://git.openjdk.org/jdk/pull/19114