fix: detect Hyper-V enlightenments on guests, not only root partitions

[Manny684]

What does this PR do?

• Add a new technique
• Add a new feature
• Add a new README translation
• Improve code
• Fix bugs
• Refactoring or code organisation
• Stylistic changes
• Sync between branches
• Other

Briefly explain what this PR does:

Fixes misdetection of QEMU/KVM guests running with Hyper-V enlightenments, which were being reported as genuine Microsoft Hyper-V.

Root cause

A QEMU/KVM guest running with Hyper-V enlightenments presents Microsoft Hv at CPUID leaf 0x40000000 (so the Windows guest uses the fast Hyper-V ABI), while KVM relocates its KVMKVMKVM signature to leaf 0x40000100. The 0x40000100 check that yields HYPERV_ENLIGHTENMENT / QEMU_KVM_HYPERV lived only in the root-partition branch of hyper_x(), which an ordinary guest never reaches.

Enlightened guests therefore fell through to the guest branch's eax() == 11 && is_hyperv_present() test, were classified HYPERV_REAL_VM and branded HYPERV; vmid_template() then saw Microsoft Hv and (since hyper_x() != HYPERV_HOST) added brand_enum::HYPERV as well. The final brand became "Microsoft Hyper-V" instead of "QEMU+KVM Hyper-V Enlightenment".
Changes

• hyper_x(): also check the 0x40000100 KVM signature in the guest branch, before the eax() == 11 Hyper-V-guest test.
• vmid_template(): when hyper_x() reports HYPERV_ENLIGHTENMENT, still flag the VM via the Microsoft Hv vendor string but don't add the misleading HYPERV brand (already set to QEMU_KVM_HYPERV by hyper_x()).

No behavior change for real Hyper-V guests/hosts, nested Hyper-V, spoofers, or bare metal.

References

• QEMU documentation confirms the leaf relocation: https://www.qemu.org/docs/master/system/i386/hyperv.html. It states: "When any set of the Hyper-V enlightenments is enabled, QEMU changes hypervisor identification (CPUID 0x40000000..0x4000000A) to Hyper-V. KVM identification and features are kept in leaves 0x40000100..0x40000101."
• KVM CPUID bits: https://docs.kernel.org/virt/kvm/x86/cpuid.html
• Prior art: systemd hit the same misdetection and fixed it the same way: QEMU with Hyper-V enlightenments incorrectly identified as Hyper-V systemd/systemd#28001

[NotRequiem]

Correct

It also should be removed from the root partition check entirely

[NotRequiem]

Thank you