mgmt: Add UP and DOWN kinds to FaceEventNotification

refs #3794

Change-Id: I3676841c004e0861c45c2cb9e0669f2091b5b372
diff --git a/src/mgmt/nfd/face-event-notification.cpp b/src/mgmt/nfd/face-event-notification.cpp
index 3422ee8..a65c7ba 100644
--- a/src/mgmt/nfd/face-event-notification.cpp
+++ b/src/mgmt/nfd/face-event-notification.cpp
@@ -179,6 +179,12 @@
     case FACE_EVENT_DESTROYED:
       os << "Kind: destroyed, ";
       break;
+    case FACE_EVENT_UP:
+      os << "Kind: up, ";
+      break;
+    case FACE_EVENT_DOWN:
+      os << "Kind: down, ";
+      break;
     }
 
   os << "FaceID: " << notification.getFaceId() << ", "
diff --git a/src/mgmt/nfd/face-event-notification.hpp b/src/mgmt/nfd/face-event-notification.hpp
index a4d1ea7..7d3121e 100644
--- a/src/mgmt/nfd/face-event-notification.hpp
+++ b/src/mgmt/nfd/face-event-notification.hpp
@@ -32,8 +32,10 @@
  * \ingroup management
  */
 enum FaceEventKind {
-  FACE_EVENT_CREATED = 1,
-  FACE_EVENT_DESTROYED = 2
+  FACE_EVENT_CREATED = 1, ///< face created
+  FACE_EVENT_DESTROYED = 2, ///< face destroyed
+  FACE_EVENT_UP = 3, ///< face went UP (from DOWN state)
+  FACE_EVENT_DOWN = 4 ///< face went DOWN (from UP state)
 };
 
 /**