RFR: JDK-8306672: support offset in dll_address_to_library_name on AIX [v2]

[JoKern65]

> So far the offset return reference parameter was not supported on AIX, but always set to -1. This could be improved, it was already supported on other OS platforms like Linux.

JoKern65 has updated the pull request incrementally with two additional commits since the last revision:

 - fix file mode bits
 - cosmetic changes

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13692/files
  - new: https://git.openjdk.org/jdk/pull/13692/files/a471510d..3b860556

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13692&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13692&range=00-01

  Stats: 7 lines in 3 files changed: 1 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/13692.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13692/head:pull/13692

PR: https://git.openjdk.org/jdk/pull/13692