qemu: hot plug block devices according with its properties

PCI devices have the addr property that correspond to the
address of the parent where the device is plugged, when this
property is set, we have to use the method to hot plug PCI
devices.

fixes #455

Signed-off-by: Julio Montes <julio.montes@intel.com>

qemu.go

@@ -849,7 +849,16 @@ func (q *qemu) hotplugBlockDevice(drive Drive, op operation) error {
 		}
 
 		driver := "virtio-blk-pci"
-		if err := q.qmpMonitorCh.qmp.ExecuteDeviceAdd(q.qmpMonitorCh.ctx, drive.ID, devID, driver, ""); err != nil {
+
+		// Addr is PCI specific, use ExecutePCIDeviceAdd if it's NOT empty
+		if drive.Addr != "" {
+			if err := q.qmpMonitorCh.qmp.ExecutePCIDeviceAdd(q.qmpMonitorCh.ctx, drive.ID, devID, driver, drive.Addr, drive.Bus); err != nil {
+				return err
+			}
+		} else {
+			if err := q.qmpMonitorCh.qmp.ExecuteDeviceAdd(q.qmpMonitorCh.ctx, drive.ID, devID, driver, drive.Bus); err != nil {
+				return err
+			}
 			return err
 		}
 	} else {