Add dummy ticket support

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 6591ecb..6e754a3 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -186,8 +186,9 @@
     if( now < session->start )
     {
         MBEDTLS_SSL_DEBUG_MSG(
-            3, ( "Ticket expired: now=%" MBEDTLS_PRINTF_LONGLONG
-                    ", start=%" MBEDTLS_PRINTF_LONGLONG,
+            3, ( "Ticket expired: start is in future "
+                    "( now=%" MBEDTLS_PRINTF_LONGLONG
+                    ", start=%" MBEDTLS_PRINTF_LONGLONG " )",
                     (long long)now, (long long)session->start ) );
         goto exit;
     }