fw: use scope_prefix::LOCALHOST in Forwarder

refs #3546

Change-Id: I10a05b642284e7466746cac121d13e7948ca8667
diff --git a/daemon/fw/pit-algorithm.cpp b/daemon/fw/pit-algorithm.cpp
index ca54dfe..ecc8acd 100644
--- a/daemon/fw/pit-algorithm.cpp
+++ b/daemon/fw/pit-algorithm.cpp
@@ -26,13 +26,13 @@
 #include "pit-algorithm.hpp"
 
 namespace nfd {
-namespace fw {
-
 namespace scope_prefix {
 const Name LOCALHOST("ndn:/localhost");
 const Name LOCALHOP("ndn:/localhop");
 } // namespace scope_prefix
 
+namespace fw {
+
 bool
 violatesScope(const pit::Entry& pitEntry, const Face& outFace)
 {