management: Update nfd::RibControlCommand::applyDefaults to reflect spec update

Change-Id: Ib64ccfa56c6304a32a72bece99040cc3a53e6404
Refs: #1722
diff --git a/src/management/nfd-control-command.hpp b/src/management/nfd-control-command.hpp
index 0068317..252812c 100644
--- a/src/management/nfd-control-command.hpp
+++ b/src/management/nfd-control-command.hpp
@@ -495,7 +495,7 @@
       .required(CONTROL_PARAMETER_ORIGIN)
       .required(CONTROL_PARAMETER_COST)
       .required(CONTROL_PARAMETER_FLAGS)
-      .required(CONTROL_PARAMETER_EXPIRATION_PERIOD);
+      .optional(CONTROL_PARAMETER_EXPIRATION_PERIOD);
   }
 
   virtual void
@@ -513,14 +513,6 @@
     if (!parameters.hasFlags()) {
       parameters.setFlags(ROUTE_FLAG_CHILD_INHERIT);
     }
-    if (!parameters.hasExpirationPeriod()) {
-      if (parameters.getFaceId() == 0) {
-        parameters.setExpirationPeriod(time::milliseconds::max());
-      }
-      else {
-        parameters.setExpirationPeriod(time::hours(1));
-      }
-    }
   }
 
   virtual void