RFR: 8360025: (se) Convert kqueue Selector Implementation to use FFM APIs

[Darragh Clarke]

This PR aims to Panamize the Java Kqueue implementation, This is based on the work that was previously shared in https://github.com/openjdk/jdk/pull/22307 , The main change since then is that this branch takes advantage of the changes made in https://github.com/openjdk/jdk/pull/25043 to allow for better performance during errno handling.

These changes feature a lot of Jextract generated files, though alterations have been made in relation to Errno handling and performance improvements.

I will update this description soon to include performance metrics on a few microbenchmarks, though currently it's roughly 2% to 3% slower with the changes, which is somewhat expected, though there are still a few ideas of possible performance improvements that could be tried. Any suggestions or comments in that area are more than welcome however.

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Commit messages:
 - feedback
 - general cleanup
 - small refactoring
 - Performance
 - implementing feedback
 - removed unrelated change
 - merge master into branch
 - panamization of kqueue

Changes: https://git.openjdk.org/jdk/pull/25546/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25546&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8360025
  Stats: 1489 lines in 14 files changed: 1306 ins; 121 del; 62 mod
  Patch: https://git.openjdk.org/jdk/pull/25546.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25546/head:pull/25546

PR: https://git.openjdk.org/jdk/pull/25546