[lworld] RFR: 8353186: [lworld] Disable failing tests after JDK-8351569

[Christian Hagedorn]

[JDK-8351569](https://bugs.openjdk.org/browse/JDK-8351569) triggered some test failures (see [JDK-8353180](https://bugs.openjdk.org/browse/JDK-8353180) and [JDK-8353182](https://bugs.openjdk.org/browse/JDK-8353182)). To reduce noise until these are fixed, I'm disabling the failing tests by either disabling IR rules or preventing certain flag modes.

Thanks,
Christian

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Commit messages:
 - 8353186: [lworld] Disable failing tests after JDK-8351569

Changes: https://git.openjdk.org/valhalla/pull/1413/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1413&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8353186
  Stats: 31 lines in 3 files changed: 16 ins; 0 del; 15 mod
  Patch: https://git.openjdk.org/valhalla/pull/1413.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1413/head:pull/1413

PR: https://git.openjdk.org/valhalla/pull/1413