RFR: 7903917: Changes needed for jdk23-based makefile build

[Nizar Benalla]

Changes necessary to bump the supported version to JDK 23.
Passes tier 1.

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Commit messages:
 - CODETOOLS-7903917

Changes: https://git.openjdk.org/jextract/pull/265/files
  Webrev: https://webrevs.openjdk.org/?repo=jextract&pr=265&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903917
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jextract/pull/265.diff
  Fetch: git fetch https://git.openjdk.org/jextract.git pull/265/head:pull/265

PR: https://git.openjdk.org/jextract/pull/265