RFR: Minor tweaks in jextract codegen

[Jorn Vernee]

On Wed, 17 Jan 2024 12:49:27 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> When running some examples, I noted that:
> 
> * jextract is not adding javadoc to the function wrappers in the header class (instead the javadoc is added to the MH getter)
> * the new `reinterpret` method still use the parameter name `scope` instead of `arena`

Marked as reviewed by jvernee (Committer).

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PR Review: https://git.openjdk.org/jextract/pull/183#pullrequestreview-1827270624