[lworld] RFR: 8326893: [lworld] update HiddenInlineClassTest and HiddenValueClass tests per JEP 401

[Mandy Chung]

`HiddenPoint.jcod` and `ValueImpl.jcod` are no longer needed.   The class bytes of a compiled value class can be used to defined as a hidden class.   `HiddenInlineClassTest` and `HiddenValueClass` tests are updated accordingly.

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Commit messages:
 - fix comment
 - 8326893: [lworld] update HiddenInlineClassTest and HiddenValueClass tests per JEP 401

Changes: https://git.openjdk.org/valhalla/pull/1025/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1025&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326893
  Stats: 387 lines in 4 files changed: 19 ins; 363 del; 5 mod
  Patch: https://git.openjdk.org/valhalla/pull/1025.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1025/head:pull/1025

PR: https://git.openjdk.org/valhalla/pull/1025