all: Fixing compatibility with NFD 0.5 and ndn-cxx 0.5

Change-Id: I3d23acf29f4858049d1040a3e421e1c7151b3aba
diff --git a/utils/dummy-keychain.hpp b/utils/dummy-keychain.hpp
index 4a1c0fd..c76b95c 100644
--- a/utils/dummy-keychain.hpp
+++ b/utils/dummy-keychain.hpp
@@ -21,6 +21,7 @@
 #define NDNSIM_UTILS_DUMMY_KEYCHAIN_HPP
 
 #include <ndn-cxx/security/key-chain.hpp>
+#include <ndn-cxx/security/security-common.hpp>
 
 namespace ndn {
 namespace security {