Add SSL presets.

No need to use a separate profile as in X.509, everything we need is already
in ssl_config. Just load appropriate values.
diff --git a/programs/ssl/mini_client.c b/programs/ssl/mini_client.c
index 090e018..2d1dcb9 100644
--- a/programs/ssl/mini_client.c
+++ b/programs/ssl/mini_client.c
@@ -191,7 +191,8 @@
 
     if( mbedtls_ssl_config_defaults( &conf,
                 MBEDTLS_SSL_IS_CLIENT,
-                MBEDTLS_SSL_TRANSPORT_STREAM) != 0 )
+                MBEDTLS_SSL_TRANSPORT_STREAM,
+                MBEDTLS_SSL_PRESET_DEFAULT ) != 0 )
     {
         ret = ssl_config_defaults_failed;
         goto exit;