RFR: JDK-8313244: NM flags handling in configure process

[Andreas Steiner]

On AIX we need the -X64 option for NM in the build. The handling is equivalent to the other used tools flags like AR.
This change will replace the quick fix done in https://bugs.openjdk.org/browse/JDK-8312466.

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Commit messages:
 - JDK-8313244: NM flags handling in configure process

Changes: https://git.openjdk.org/jdk/pull/15150/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15150&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313244
  Stats: 22 lines in 5 files changed: 14 ins; 6 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/15150.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15150/head:pull/15150

PR: https://git.openjdk.org/jdk/pull/15150