tls13:server:Add finalize write_server_hello and dummy body

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 8254e9d..ccc66a9 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -759,6 +759,21 @@
     return( ret );
 }
 
+static int ssl_tls13_write_client_hello_body( mbedtls_ssl_context *ssl,
+                                              unsigned char *buf,
+                                              unsigned char *end,
+                                              size_t *out_len )
+{
+    return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
+}
+
+
+static int ssl_tls13_finalize_server_hello( mbedtls_ssl_context *ssl )
+{
+    mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_ENCRYPTED_EXTENSIONS );
+    return( 0 );
+}
+
 static int ssl_tls13_write_server_hello( mbedtls_ssl_context *ssl )
 {
     int ret = 0;