mgmt: LpFace faces/enable-local-control workaround

In this temporary workaround,
faces/enable-local-control enables all local fields in GenericLinkService,
and faces/disable-local-control disables all local fields in GenericLinkService.

This commit also modifies FaceTable::remove to retain shared_ptr<Face>
until signal execution is complete.

refs #3226

Change-Id: I3513e97ec2af87df94dbf57a7256b895ed9d2103
diff --git a/daemon/mgmt/face-manager.hpp b/daemon/mgmt/face-manager.hpp
index f5283d6..e3c955f 100644
--- a/daemon/mgmt/face-manager.hpp
+++ b/daemon/mgmt/face-manager.hpp
@@ -36,6 +36,10 @@
 class NetworkInterfaceInfo;
 class ProtocolFactory;
 
+namespace face {
+class LpFace;
+} // namespace face
+
 /**
  * @brief implement the Face Management of NFD Management Protocol.
  * @sa http://redmine.named-data.net/projects/nfd/wiki/FaceMgmt
@@ -88,6 +92,7 @@
   {
     bool isValid;
     shared_ptr<LocalFace> face;
+    face::LpFace* lpFace;
     LocalControlFeature feature;
   };