nodedev: add DEFINED/UNDEFINED lifecycle events

Since a mediated device can be persistently defined by the mdevctl
backend, we need additional lifecycle events beyond CREATED/DELETED to
indicate that e.g. the device has been stopped but the device definition
still exists.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>

examples/c/misc/event-test.c

@@ -381,6 +381,10 @@ nodeDeviceEventToString(int event)
             return "Created";
         case VIR_NODE_DEVICE_EVENT_DELETED:
             return "Deleted";
+        case VIR_NODE_DEVICE_EVENT_DEFINED:
+            return "Defined";
+        case VIR_NODE_DEVICE_EVENT_UNDEFINED:
+            return "Undefined";
         case VIR_NODE_DEVICE_EVENT_LAST:
             break;
     }