The user of page_track might needs extra information, so pass
the kvm_page_track_notifier_node to callbacks.
Signed-off-by: NJike Song <jike.song@intel.com>
Reviewed-by: NXiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>