[jfx25u] RFR: 8368691: Update libxml2 to 2.14.6

Mon Oct 6 13:26:29 UTC 2025

Clean Backport. Updated libxml2 to v2.14.6. Verified build and sanity on all platforms.

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Commit messages:
 - Backport 6ab42f99914c1d1e504432957aba992e2b98e377

Changes: https://git.openjdk.org/jfx25u/pull/22/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx25u&pr=22&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8368691
  Stats: 123 lines in 16 files changed: 74 ins; 11 del; 38 mod
  Patch: https://git.openjdk.org/jfx25u/pull/22.diff
  Fetch: git fetch https://git.openjdk.org/jfx25u.git pull/22/head:pull/22

PR: https://git.openjdk.org/jfx25u/pull/22