RFR: 8326685: Linux builds not reproducible if two builds configured in different build folders

[Andrew Leonard]

Adds Linux -fdebug-prefix-map'ing for SUPPORT_OUTPUTDIR and HOTSPOT_OUTPUTDIR when absolute paths are not allowed in the binaries, thus making the building of a JDK identically reproducible from different build directories.

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Commit messages:
 - 8326685: Linux builds not reproducible if two builds configured in different build folders

Changes: https://git.openjdk.org/jdk/pull/18009/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18009&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326685
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/18009.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18009/head:pull/18009

PR: https://git.openjdk.org/jdk/pull/18009