RFR: [type-classes] 8378114: Cleanup equals and hashCode for Numerical types

[Joe Darcy]

Cleanup equals/hashCode.

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Commit messages:
 - 8378114: Cleanup equals and hashCode for Numerical types

Changes: https://git.openjdk.org/valhalla/pull/2121/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=2121&range=00
  Stats: 52 lines in 2 files changed: 30 ins; 0 del; 22 mod
  Patch: https://git.openjdk.org/valhalla/pull/2121.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2121/head:pull/2121

PR: https://git.openjdk.org/valhalla/pull/2121