[lworld] RFR: 8247569: [lworld] Align with spec for <vnew> methods [v6]

[Vicente Romero]

> Value classes constructor should be named <vnew> instead of <init>. This PR can't be pushed without the corresponding support being available on the VM side

Vicente Romero has updated the pull request incrementally with one additional commit since the last revision:

  adding regression tests

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

Changes:
  - all: https://git.openjdk.org/valhalla/pull/771/files
  - new: https://git.openjdk.org/valhalla/pull/771/files/f984f661..7f01be1a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=771&range=05
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=771&range=04-05

  Stats: 108 lines in 1 file changed: 108 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/valhalla/pull/771.diff
  Fetch: git fetch https://git.openjdk.org/valhalla pull/771/head:pull/771

PR: https://git.openjdk.org/valhalla/pull/771