Add load-save tests for tls13

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index b074d58..d185aa7 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -4768,7 +4768,8 @@
 /* END_CASE */
 
 /* BEGIN_CASE */
-void ssl_serialize_session_load_save( int ticket_len, char *crt_file )
+void ssl_serialize_session_load_save( int ticket_len, char *crt_file,
+                                      int endpoint_type, int tls_version )
 {
     mbedtls_ssl_session session;
     unsigned char *buf1 = NULL, *buf2 = NULL;
@@ -4781,7 +4782,20 @@
     mbedtls_ssl_session_init( &session );
 
     /* Prepare a dummy session to work on */
-    TEST_ASSERT( ssl_tls12_populate_session( &session, ticket_len, crt_file ) == 0 );
+    ((void) endpoint_type);
+    ((void) tls_version);
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
+    if(tls_version == MBEDTLS_SSL_VERSION_TLS1_3)
+    {
+        TEST_ASSERT( ssl_tls13_populate_session(
+                         &session, 0, endpoint_type ) == 0 );
+    }
+    else
+#endif
+    {
+        TEST_ASSERT( ssl_tls12_populate_session(
+                         &session, ticket_len, crt_file ) == 0 );
+    }
 
     /* Get desired buffer size for serializing */
     TEST_ASSERT( mbedtls_ssl_session_save( &session, NULL, 0, &len0 )