RFR: Update code to use address target layouts

[Jorn Vernee]

On Mon, 30 Jan 2023 17:38:54 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

> This patch tweaks jextract to replace usages of `OfAddress.asUnbounded` with:
> 
> `withTargetLayout(sequenceLayout(JAVA_BYTE))`

Marked as reviewed by jvernee (no project role).

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

PR: https://git.openjdk.org/jextract/pull/100