AN539 : Remove AN539 from code-base

This patch removes mps2/an539 from the code-base and the documentation.

Signed-off-by: Hugo L'Hostis <hugo.lhostis@arm.com>
Change-Id: I191e04bf51c729056efd2adee0c3db72ae6eb23c
diff --git a/docs/getting_started/tfm_secure_boot.rst b/docs/getting_started/tfm_secure_boot.rst
index 03175f2..eeb2cca 100644
--- a/docs/getting_started/tfm_secure_boot.rst
+++ b/docs/getting_started/tfm_secure_boot.rst
@@ -232,8 +232,6 @@
 +---------------------+-----------------+---------------+----------+----------------+--------------+
 | AN519               | Yes             | Yes           | Yes      | Yes            | No           |
 +---------------------+-----------------+---------------+----------+----------------+--------------+
-| AN539               | Yes             | Yes           | Yes      | Yes            | No           |
-+---------------------+-----------------+---------------+----------+----------------+--------------+
 | FVP_SSE300_MPS2     | No              | Yes           | Yes      | Yes            | No           |
 +---------------------+-----------------+---------------+----------+----------------+--------------+
 | FVP_SSE300_MPS3     | No              | Yes           | Yes      | Yes            | No           |
@@ -793,4 +791,4 @@
 
 --------------
 
-*Copyright (c) 2018-2020, Arm Limited. All rights reserved.*
+*Copyright (c) 2018-2021, Arm Limited. All rights reserved.*