[lworld] RFR: 8373701: [lworld] Revert Use Objects.equals in HashMap and ConcurrentHashmap

[Roger Riggs]

Revert the use of Objects.equals to the previous explicit `==` check for identity and conditional call to .equals. The use of Objects.equals (without identity) caused classes with poorly written .equals methods to work incorrectly with HashMap and ConcurrentHashMap.

This reverts commit c8d4a247861052aa6ed43125bcbe49995326938f.

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Commit messages:
 - Revert "8366214: [lworld] Use Objects.equals in HashMap and ConcurrentHashmap"

Changes: https://git.openjdk.org/valhalla/pull/1800/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1800&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373701
  Stats: 45 lines in 2 files changed: 7 ins; 1 del; 37 mod
  Patch: https://git.openjdk.org/valhalla/pull/1800.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1800/head:pull/1800

PR: https://git.openjdk.org/valhalla/pull/1800