RFR: 8326685: Linux builds not reproducible if two builds configured in different build folders [v2]

[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.

Andrew Leonard has updated the pull request incrementally with two additional commits since the last revision:

 - 8326685: Linux builds not reproducible if two builds configured in different build folders
   
   Signed-off-by: Andrew Leonard <anleonar at redhat.com>
 - 8326685: Linux builds not reproducible if two builds configured in different build folders
   
   Signed-off-by: Andrew Leonard <anleonar at redhat.com>

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/18009/files
  - new: https://git.openjdk.org/jdk/pull/18009/files/d3200dd3..4bd1d3dd

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18009&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18009&range=00-01

  Stats: 5 lines in 1 file changed: 3 ins; 0 del; 2 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