New sample program to benchmark certificate loading

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/programs/x509/CMakeLists.txt b/programs/x509/CMakeLists.txt
index 29cbeb8..5b1c319 100644
--- a/programs/x509/CMakeLists.txt
+++ b/programs/x509/CMakeLists.txt
@@ -15,6 +15,7 @@
     cert_req
     cert_write
     crl_app
+    load_roots
     req_app
 )