[crac] RFR: Fix up CPUFeatures on top of Merge jdk:jdk-25+26 [v2]

[Jan Kratochvil]

On Fri, 25 Jul 2025 12:53:03 GMT, Timofei Pushkin <tpushkin at openjdk.org> wrote:

> features_missing could be a const reference.

AI says:
> For a 16‑byte struct on a 64‑bit system, passing by value is usually faster or equal, and passing by const& rarely improves performance.

But it became a method now so it became a pointer anyway.

`/*[[noreturn]]*/` was obsolete, thanks for catching it.

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PR Review Comment: https://git.openjdk.org/crac/pull/250#discussion_r2231582073