RFR: 8376703: Some coding in libjimage seems to be not called at all or not called from PRODUCT code

[Matthias Baesken]

libjimage has a few unused functions/methods; those are listed when logging elimination with  -Wl,--gc-sections -Wl,--print-gc-sections .
We could remove them (or with if are still needed for completeness  put them into  #if 0 ) to reduce lib size on Linux and AIX.
On Windows and macOS it seems the compiler/linker default settings are good enough to eliminate the code.

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Commit messages:
 - JDK-8376703

Changes: https://git.openjdk.org/jdk/pull/29502/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29502&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8376703
  Stats: 69 lines in 5 files changed: 0 ins; 69 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/29502.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29502/head:pull/29502

PR: https://git.openjdk.org/jdk/pull/29502