fib: implicitly delete empty Entry

Fib::removeNextHopFromAllEntries automatically deletes fib::Entry
if the last nexthop record is being removed.

refs #1341

Change-Id: I36d42fe8f9fc8f03d194f845020aff408cd70488
diff --git a/daemon/table/name-tree.cpp b/daemon/table/name-tree.cpp
index 5d11c27..430ed3c 100644
--- a/daemon/table/name-tree.cpp
+++ b/daemon/table/name-tree.cpp
@@ -498,8 +498,10 @@
         }
 
       // process other buckets
-      int newLocation = m_entry->m_hash % m_nameTree.m_nBuckets + 1;
-      for (newLocation = newLocation; newLocation < m_nameTree.m_nBuckets; newLocation++)
+
+      for (int newLocation = m_entry->m_hash % m_nameTree.m_nBuckets + 1;
+           newLocation < static_cast<int>(m_nameTree.m_nBuckets);
+           ++newLocation)
         {
           // process each bucket
           name_tree::Node* node = m_nameTree.m_buckets[newLocation];
@@ -637,6 +639,9 @@
       m_entry = m_nameTree.m_end;
       return *this;
     }
+
+  BOOST_ASSERT(false); // unknown type
+  return *this;
 }
 
 } // namespace nfd