RFR: 8290066: Remove KNL specific handling for new CPU target check in IR annotation

[Jatin Bhateja]

- Newly added annotations query the CPU feature using white box API which returns the list of features enabled during VM initialization.
- With JVM flag UseKNLSetting, during VM initialization AVX512 features not supported by KNL target are disabled, thus we do not need any special handling for KNL in newly introduced IR annotations (applyCPUFeature, applyCPUFeatureOr, applyCPUFeatureAnd).

Please review and share your feedback.

Best Regards,
Jatin

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

Commit messages:
 - 8290066: Remove KNL specific handling for new CPU feature IR annotations

Changes: https://git.openjdk.org/jdk/pull/9452/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9452&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8290066
  Stats: 192 lines in 5 files changed: 83 ins; 108 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/9452.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9452/head:pull/9452

PR: https://git.openjdk.org/jdk/pull/9452