CVE-2026-89912 KVM: arm64: vgic-its: Don't dereference a NULL collection on ITT save

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Don't dereference a NULL collection on ITT save MAPC with V=0 drops ite-collection but leaves the ITE on the device's ITT list, and vgicitssaveite dereferences it unconditionally. A guest that issues MAPD,...