RFR: 8341282: (fs) Move creation time fallback logic to Java layer (Linux) [v2]

[Brian Burkhalter]

> Move the decision as to whether `BasicFileAttributes.creationTime()` falls back to the modified time from the native layer to the Java layer.

Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:

  8341282: birthtime_invalid -> birthtime_available

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Changes:
  - all: https://git.openjdk.org/jdk/pull/21274/files
  - new: https://git.openjdk.org/jdk/pull/21274/files/c36d867a..e0bd5b07

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21274&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21274&range=00-01

  Stats: 17 lines in 2 files changed: 1 ins; 0 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/21274.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21274/head:pull/21274

PR: https://git.openjdk.org/jdk/pull/21274