Update gennews for GCC 10.

2020-05-07  Jakub Jelinek  <jakub@redhat.com>

	* gennews (files): Add files for GCC 10.

contrib/ChangeLog

+2020-05-07  Jakub Jelinek  <jakub@redhat.com>
+
+	* gennews (files): Add files for GCC 10.
+
 2020-04-17  Martin Liska  <mliska@suse.cz>
 
 	* vimrc: We do not want to modify tab options

contrib/gennews

@@ -3,7 +3,7 @@
 # Script to generate the NEWS file from online release notes.
 # Contributed by Joseph Myers <jsm28@cam.ac.uk>.
 #
-# Copyright (C) 2000-2019 Free Software Foundation, Inc.
+# Copyright (C) 2000-2020 Free Software Foundation, Inc.
 # This file is part of GCC.
 #
 # GCC is free software; you can redistribute it and/or modify
@@ -23,6 +23,7 @@
 
 website=http://gcc.gnu.org/
 files="
+    gcc-10/index.html gcc-10/changes.html
     gcc-9/index.html gcc-9/changes.html
     gcc-8/index.html gcc-8/changes.html
     gcc-7/index.html gcc-7/changes.html