[jdk21u-dev] RFR: 8317240: Promptly free OopMapEntry after fail to insert the entry to OopMapCache

[Aleksey Shipilev]

Improves `OopMapCache` performance by skipping enqueuing when we can deallocate the entry directly. This would be even more important as we backport [JDK-8331572](https://bugs.openjdk.org/browse/JDK-8331572).

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

-------------

Commit messages:
 - Backport a8eacb31ab8466f50a939d6748dbdd1560516878

Changes: https://git.openjdk.org/jdk21u-dev/pull/655/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=655&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317240
  Stats: 17 lines in 1 file changed: 6 ins; 5 del; 6 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/655.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/655/head:pull/655

PR: https://git.openjdk.org/jdk21u-dev/pull/655