RFR: 8337716: ByteBuffer hashCode implementations are inconsistent

[Brian Burkhalter]

Revert the changes made in #16992 and add some test coverage.

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Commit messages:
 - 8337716: ByteBuffer hashCode implementations are inconsistent

Changes: https://git.openjdk.org/jdk/pull/20451/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20451&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8337716
  Stats: 38 lines in 3 files changed: 24 ins; 12 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20451.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20451/head:pull/20451

PR: https://git.openjdk.org/jdk/pull/20451