RFR: 8360887: [AIX] getFileAttributeView returns unusable FileAttributeView if UserDefinedFileAttributeView unavailable

[Martin Doerr]

We need to fix this wrong behavior on AIX and the test should cover it. Please review!

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Commit messages:
 - 8360887: [AIX] getFileAttributeView returns unusable FileAttributeView if UserDefinedFileAttributeView unavailable

Changes: https://git.openjdk.org/jdk/pull/26021/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26021&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8360887
  Stats: 18 lines in 2 files changed: 14 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/26021.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26021/head:pull/26021

PR: https://git.openjdk.org/jdk/pull/26021