Merge tag 'kvm-x86-sev-6.17' of https://github.com/kvm-x86/linux into HEAD

KVM SEV cache maintenance changes for 6.17

 - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM.

 - Use WBNOINVD instead of WBINVD when possible, for SEV cache maintenance,
   e.g. to minimize collateral damage when reclaiming memory from an SEV guest.

 - When reclaiming memory from an SEV guest, only do cache flushes on CPUs that
   have ever run a vCPU for the guest, i.e. don't flush the caches for CPUs
   that can't possibly have cache lines with dirty, encrypted data.