[jdk25u] RFR: 8363966: GHA: Switch cross-compiling sysroots to Debian trixie

[Aleksey Shipilev]

Enables up-to-date and consistent cross-compilation across all arches.

Additional testing:
 - [ ] GHA

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Commit messages:
 - Backport 2a5f149bb8e26277778465fff670591c929842de

Changes: https://git.openjdk.org/jdk25u/pull/200/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u&pr=200&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8363966
  Stats: 6 lines in 1 file changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk25u/pull/200.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u.git pull/200/head:pull/200

PR: https://git.openjdk.org/jdk25u/pull/200