Changelog in v6: -Moved CONFIG_KVM_FREE_PAGE_HINTING from virt/kvm/Kconfig to arch/x86/kvm/Kconfig in order to resolve conflicts with other architectures: *s390 has its own page hinting functionality *powerpc has its own arch_free_page implementation -Fixed the typo in virtio_balloon structure which caused compilation issues when guest page hinting was disabled -Separated init_vqs implementation with and without hinting_vq enablement based on the CONFIG_KVM_FREE_PAGE_HINTING ifdef Virtio interface changes are picked up from Wei's patch-set for Virtio-balloon enhancement[3]. "Wei, How would you like me to credit you in the final patch?")
