tools: nfdc strategy set/unset commands

nfdc set-strategy and nfdc unset-strategy are deprecated.

refs #3865

Change-Id: I934cbfcd567ac7ee33381ae4baf00b668977a0aa
diff --git a/tools/nfdc/available-commands.cpp b/tools/nfdc/available-commands.cpp
index a1d22cb..0d4847f 100644
--- a/tools/nfdc/available-commands.cpp
+++ b/tools/nfdc/available-commands.cpp
@@ -58,8 +58,8 @@
     {"unregister", "unregister a prefix", "route remove"},
     {"create", "create a face", "face create"},
     {"destroy", "destroy a face", "face destroy"},
-    {"set-strategy", "set strategy choice on namespace", ""},
-    {"unset-strategy", "unset strategy choice on namespace", ""},
+    {"set-strategy", "set strategy choice on namespace", "strategy set"},
+    {"unset-strategy", "unset strategy choice on namespace", "strategy unset"},
     {"add-nexthop", "add FIB nexthop", "route add"},
     {"remove-nexthop", "remove FIB nexthop", "route remove"}
   };