Add define to fuzz/common.c and ssl/ssl_test_lib.c

Signed-off-by: Felix Conway <felix.conway@arm.com>
diff --git a/programs/ssl/ssl_test_lib.c b/programs/ssl/ssl_test_lib.c
index acc01a2..6aa60fb 100644
--- a/programs/ssl/ssl_test_lib.c
+++ b/programs/ssl/ssl_test_lib.c
@@ -8,6 +8,7 @@
  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
  */
 
+#define MBEDTLS_DECLARE_PRIVATE_IDENTIFIERS
 
 #include "ssl_test_lib.h"