[foreign-jextract] RFR: 8248710: jextract should not generate Cstring, Cpointer, Cint C-X utility classes [v3]

[Athijegannathan Sundararajan]

> Cstring, Cpointer, C-X* classes are not generated anymore. Updated tests, samples for the same. Samples updated for
> stability issues with foreign-abi crashes as well.

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

  removed allocatePointer helper to simplify the test and the sample code.

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

Changes:
  - all: https://git.openjdk.java.net/panama-foreign/pull/228/files
  - new: https://git.openjdk.java.net/panama-foreign/pull/228/files/d5b8ee0a..b649bdc1

Webrevs:
 - full: https://webrevs.openjdk.java.net/panama-foreign/228/webrev.02
 - incr: https://webrevs.openjdk.java.net/panama-foreign/228/webrev.01-02

  Stats: 160 lines in 3 files changed: 5 ins; 32 del; 123 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/228.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/228/head:pull/228

PR: https://git.openjdk.java.net/panama-foreign/pull/228