KVM: enable PCI multiple-segments for pass-through device

Enable optional parameter (default 0) - PCI segment (or domain) besides
BDF, when assigning PCI device to guest.

Signed-off-by: Zhai Edwin <edwin.zhai@intel.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index dfde04b..665c370 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -400,6 +400,7 @@
 	struct work_struct interrupt_work;
 	struct list_head list;
 	int assigned_dev_id;
+	int host_segnr;
 	int host_busnr;
 	int host_devfn;
 	unsigned int entries_nr;