face: simplify prefix registration APIs with SigningInfo

refs #2932

Change-Id: I9a29cf2925272b9fc90b4fb69a14035a75291928
diff --git a/src/security/conf/checker.hpp b/src/security/conf/checker.hpp
index 3c4ceb2..1364229 100644
--- a/src/security/conf/checker.hpp
+++ b/src/security/conf/checker.hpp
@@ -29,6 +29,7 @@
 #include "key-locator-checker.hpp"
 #include "../../util/io.hpp"
 #include "../validator.hpp"
+#include "../identity-certificate.hpp"
 
 #include <boost/algorithm/string.hpp>
 #include <boost/filesystem.hpp>