Improve and simplify code with modern C++ features

Change-Id: I83bf5513c2a1f90ba5a59e93c473306864b27d94
diff --git a/daemon/table/name-tree-iterator.cpp b/daemon/table/name-tree-iterator.cpp
index 56c0360..f295d9c 100644
--- a/daemon/table/name-tree-iterator.cpp
+++ b/daemon/table/name-tree-iterator.cpp
@@ -46,7 +46,7 @@
 }
 
 Iterator::Iterator(shared_ptr<EnumerationImpl> impl, const Entry* ref)
-  : m_impl(impl)
+  : m_impl(std::move(impl))
   , m_entry(nullptr)
   , m_ref(ref)
   , m_state(0)