Merge tag 'kvm-x86-svm-6.15' of https://github.com/kvm-x86/linux into HEAD

KVM SVM changes for 6.15

 - Ensure the PSP driver is initialized when both the PSP and KVM modules are
   built-in (the initcall framework doesn't handle dependencies).

 - Use long-term pins when registering encrypted memory regions, so that the
   pages are migrated out of MIGRATE_CMA/ZONE_MOVABLE and don't lead to
   excessive fragmentation.

 - Add macros and helpers for setting GHCB return/error codes.

 - Add support for Idle HLT interception, which elides interception if the vCPU
   has a pending, unmasked virtual IRQ when HLT is executed.

 - Fix a bug in INVPCID emulation where KVM fails to check for a non-canonical
   address.

 - Don't attempt VMRUN for SEV-ES+ guests if the vCPU's VMSA is invalid, e.g.
   because the vCPU was "destroyed" via SNP's AP Creation hypercall.

 - Reject SNP AP Creation if the requested SEV features for the vCPU don't
   match the VM's configured set of features.

 - Misc cleanups