Use 0x40000010 CPUID leaf to announce frequencies

[cperciva]

The 0x40000010 CPUID leaf is used to announce TSC and local APIC frequencies to VM guests; this allows them to boot faster by bypassing clock calibration loops.

Changes

In x86_64 initialization, passes the TSC frequency to cpuid.normalize, which then (a) updates the 0x40000000 CPUID leaf to announce support for leaves up to 0x40000010, and (b) adds a 0x40000010 CPUID leaf to announce the TSC frequency and LAPIC frequency (which is always 10^6 in KVM).

Reason

Improve boot performance. This leaf is already used in most other hypervisors, including EC2.

License Acceptance

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PR Checklist

• [N/A] If a specific issue led to this PR, this PR closes the issue.
• [X] The description of changes is clear and encompassing.
• [N/A] Any required documentation changes (code and docs) are included in this PR.
• [N/A] API changes follow the Runbook for Firecracker API changes.
• [N/A] User-facing changes are mentioned in CHANGELOG.md.
• [ ] All added/changed functionality is tested.
• [ ] New TODOs link to an issue.
• [x] Commits meet contribution quality standards.

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• [x] This functionality cannot be added in rust-vmm.