[foreign-jextract] RFR: 8266682: sync jextract for LibraryLookup removal [v4]

[Athijegannathan Sundararajan]

> Using System.load/.loadLibrary in generated code and jextract code. Class initialisation dummy method to take sure constants classes initialise header-class before looking up names.

Athijegannathan Sundararajan has updated the pull request incrementally with one additional commit since the last revision:

  simplified loading

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

Changes:
  - all: https://git.openjdk.java.net/panama-foreign/pull/529/files
  - new: https://git.openjdk.java.net/panama-foreign/pull/529/files/7bc40d67..9890eda0

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=529&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=529&range=02-03

  Stats: 19 lines in 2 files changed: 8 ins; 8 del; 3 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/529.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/529/head:pull/529

PR: https://git.openjdk.java.net/panama-foreign/pull/529