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

KVM x86 misc changes for 6.15:

 - Fix a bug in PIC emulation that caused KVM to emit a spurious KVM_REQ_EVENT.

 - Add a helper to consolidate handling of mp_state transitions, and use it to
   clear pv_unhalted whenever a vCPU is made RUNNABLE.

 - Defer runtime CPUID updates until KVM emulates a CPUID instruction, to
   coalesce updates when multiple pieces of vCPU state are changing, e.g. as
   part of a nested transition.

 - Fix a variety of nested emulation bugs, and add VMX support for synthesizing
   nested VM-Exit on interception (instead of injecting #UD into L2).

 - Drop "support" for PV Async #PF with proctected guests without SEND_ALWAYS,
   as KVM can't get the current CPL.

 - Misc cleanups