chore: update notice (#549)

Updates `NOTICE`.

Signed-off-by: Ryan Johnson <ryan.johnson@broadcom.com>

NOTICE

@@ -1,12 +1,12 @@
-terraform-provider-vra
+© Broadcom. All Rights Reserved.
+The term "Broadcom" refers to Broadcom Inc. and/or its subsidiaries.
+SPDX-License-Identifier: MPL-2.0
 
-Copyright 2019-2021 VMware, Inc. All Rights Reserved.
+This product is licensed to you under the Mozilla Public license, Version 2.0
+(the "License"). You may not use this product except in compliance with the
+Mozilla Public License.
 
-This product is licensed to you under the Mozilla Public License, version 2.0
-license (the "License"). You may not use this product except in compliance
-with the MPL 2 License.
-
-This product may include a number of subcomponents with separate
-copyright notices and license terms. Your use of these subcomponents
-is subject to the terms and conditions of the subcomponent's license,
-as noted in the LICENSE file.
+This product may include a number of subcomponents with separate copyright
+notices and license terms. Your use of these subcomponents is subject to the
+terms and conditions of the subcomponent's license, as noted in the LICENSE
+file.