RFR: Add path independence

Wed Aug 31 07:23:06 UTC 2022

This small PR incorporated feedback from the original PR: https://github.com/openjdk/jextract/pull/66 made after it was integrated.

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Commit messages:
 - Add path independence

Changes: https://git.openjdk.org/jextract/pull/68/files
 Webrev: https://webrevs.openjdk.org/?repo=jextract&pr=68&range=00
  Stats: 10 lines in 4 files changed: 2 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jextract/pull/68.diff
  Fetch: git fetch https://git.openjdk.org/jextract pull/68/head:pull/68

PR: https://git.openjdk.org/jextract/pull/68