build: suppress CryptoPP warnings

Change-Id: I52e93fb18c42cf72d73c4477dc4a8093a5221215
diff --git a/tools/ndnsec-util.hpp b/tools/ndnsec-util.hpp
index 0934d90..afc393a 100644
--- a/tools/ndnsec-util.hpp
+++ b/tools/ndnsec-util.hpp
@@ -22,8 +22,7 @@
 #include <boost/exception/all.hpp>
 
 
-#include <cryptopp/base64.h>
-#include <cryptopp/files.h>
+#include "security/cryptopp.hpp"
 
 #include "security/key-chain.hpp"
 #include "util/io.hpp"