RFR: 8367780: Enable UseAPX on Intel CPUs only when both APX_F and APX_NCI_NDD_NF cpuid features are present

[Srinivas Vamsi Parasa]

The goal of this PR is to enable APX on Intel CPUs (i.e. enable UseAPX) only when both the APX_F and APX_NCI_NDD_NF cpuid feature flags are present.

As per the latest update to the Intel APX specification (https://www.intel.com/content/www/us/en/content-details/861610/intel-advanced-performance-extensions-intel-apx-architecture-specification.html ), when APX_F is set, processors also provide CPUID leaf 0x29 (APX Advanced Performance Extensions Leaf). Any Intel processor that enumerates APX_F also enumerates APX_NCI_NDD_NF.

This PR enhances the HotSpot x86 CPU feature detection to recognize the APX_NCI_NDD_NF sub-feature of Intel APX and update the enabling logic for UseAPX VM flag.

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Commit messages:
 - clean up
 - 8367780: Enable UseAPX on Intel CPUs only when both APX_F and APX_NCI_NDD_NF cpuid features are present

Changes: https://git.openjdk.org/jdk/pull/27320/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27320&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8367780
  Stats: 40 lines in 4 files changed: 33 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/27320.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27320/head:pull/27320

PR: https://git.openjdk.org/jdk/pull/27320