docs(changelog): changelog for v2.13 release

Generated this change-log using below command:
npm run release -- --skip.commit --skip.tag --release-as 2.13.0

Change-Id: Ibb0623f04c641b65a03deaffd50a5a8b65637419
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
diff --git a/docs/conf.py b/docs/conf.py
index 3a7264f..6e08030 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 #
-# Copyright (c) 2019-2024, Arm Limited. All rights reserved.
+# Copyright (c) 2019-2025, Arm Limited. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -14,8 +14,8 @@
 
 project = "Trusted Firmware-A"
 author = "Trusted Firmware-A contributors"
-version = "2.12.0"
-release = "2.12.0"
+version = "2.13.0"
+release = "2.13.0"
 
 # -- General configuration ---------------------------------------------------