[foreign-jextract] [Rev 01] RFR: 8242465: jextract should skip variables and struct fields with types that cannot be handled

[Athijegannathan Sundararajan]

> skipping problematic variables, generating empty structs for structs with problematic fields.

Athijegannathan Sundararajan has updated the pull request with a new target base due to a merge or a rebase. The pull
request now contains four commits:

 - Merge foreign-jextract
 - 8242465: jextract should skip variables and struct fields with types that cannot be handled
 - avoiding toJavaArray. printing by accessing native array directly (Cdouble's indexed getter)
 - 8242376: update jextract samples to avoid --filter option

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Changes: https://git.openjdk.java.net/panama-foreign/pull/108/files
 Webrev: https://webrevs.openjdk.java.net/panama-foreign/108/webrev.01
  Stats: 147 lines in 5 files changed: 137 ins; 0 del; 10 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/108.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/108/head:pull/108

PR: https://git.openjdk.java.net/panama-foreign/pull/108