[lworld] RFR: 8326719: [lworld] Migrate core-libs support to JEP 401 (part 1) [v2]

[Mandy Chung]

> This patch includes:
> - Removal of support for secondary mirror
> - Removal of support for primitive classes
> - Removal of support for value factories 
> - Removal of the intrinsic methods `Class::asPrimitiveType` and `asValueType`
> 
> This patch includes a temporary fix of `Class::isValue` which will be replaced by #1019.

Mandy Chung has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Unsafe::getReference no need to handle zero instance
 - Merge branch 'lworld' of https://github.com/openjdk/valhalla into dual-mirror
 - 8326719: [lworld] Migrate core-libs support to JEP 401 (part 1)

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

Changes:
  - all: https://git.openjdk.org/valhalla/pull/1020/files
  - new: https://git.openjdk.org/valhalla/pull/1020/files/7a87e78c..d601ef26

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=valhalla&pr=1020&range=01
 - incr: https://webrevs.openjdk.org/?repo=valhalla&pr=1020&range=00-01

  Stats: 58 lines in 5 files changed: 25 ins; 31 del; 2 mod
  Patch: https://git.openjdk.org/valhalla/pull/1020.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1020/head:pull/1020

PR: https://git.openjdk.org/valhalla/pull/1020