RFR: 8339783: Implement JEP 479: Remove the Windows 32-bit x86 Port [v26]

[Magnus Ihse Bursie]

> This is the implementation of [JEP 479: _Remove the Windows 32-bit x86 Port_](https://openjdk.org/jeps/479).
> 
> This is the summary of JEP 479:
>> Remove the source code and build support for the Windows 32-bit x86 port. This port was [deprecated for removal in JDK 21](https://openjdk.org/jeps/449) with the express intent to remove it in a future release.

Magnus Ihse Bursie has updated the pull request incrementally with one additional commit since the last revision:

  [JNI/JVM/AGENT]_[ONLOAD/ONUNLOAD/ONATTACH]_SYMBOLS are now identical on Windows and Unix, so unify them

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/21744/files
  - new: https://git.openjdk.org/jdk/pull/21744/files/88d89e75..6f690d02

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21744&range=25
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21744&range=24-25

  Stats: 21 lines in 3 files changed: 7 ins; 14 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/21744.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21744/head:pull/21744

PR: https://git.openjdk.org/jdk/pull/21744