Docs: Fix Armclang toolchain descriptions

- Fix Armclang PATH setting
- Specify valid Armclang versions. It is found Armclang v6.15 and v6.16
  may also cause MemManage Fault as v6.17 does.

Change-Id: Id5a591a8d165c78adf5fd9346c962662f151d496
Signed-off-by: David Hu <david.hu@arm.com>
diff --git a/docs/getting_started/tfm_getting_started.rst b/docs/getting_started/tfm_getting_started.rst
index 9314610..09bd995 100644
--- a/docs/getting_started/tfm_getting_started.rst
+++ b/docs/getting_started/tfm_getting_started.rst
@@ -115,7 +115,7 @@
 be available in the build environment. The currently supported compiler
 versions are:
 
-    - Arm Compiler v6.10.1+
+    - Arm Compiler v6.10.1 ~ v6.14.1
 
       .. tabs::
 
@@ -126,9 +126,11 @@
 
                 .. code-block:: bash
 
-                    export PATH=<ARM_CLANG_PATH>/sw/ARMCompiler6.10.1/bin:$PATH
+                    export PATH=<ARM_CLANG_PATH>/bin:$PATH
                     export ARM_PRODUCT_PATH=<ARM_CLANG_PATH>/sw/mappings
 
+              - Configure proper tool variant and license.
+
           .. group-tab:: Windows
 
               - Download the standalone packages from `here <https://developer.arm.com/products/software-development-tools/compilers/arm-compiler/downloads/version-6>`__.
@@ -136,13 +138,15 @@
 
                 .. code-block:: bash
 
-                    set PATH=<ARM_CLANG_PATH>\sw\ARMCompiler6.10.1\bin;$PATH
+                    set PATH=<ARM_CLANG_PATH>\bin;$PATH
                     set ARM_PRODUCT_PATH=<ARM_CLANG_PATH>\sw\mappings
 
+              - Configure proper tool variant and license.
+
       .. note::
 
-          ArmClang compiler *v6.17* may cause MemManage fault in TF-M higher level isolations.
-          The issue is under investigation and recommended to avoid using this version.
+          Arm compiler starting from *v6.15* may cause MemManage fault in TF-M higher isolation levels.
+          The issue is under investigation and recommended to using versions prior to v6.15.
 
     - GNU Arm compiler v7.3.1+
 
@@ -403,4 +407,4 @@
 
 --------------
 
-*Copyright (c) 2017-2021, Arm Limited. All rights reserved.*
+*Copyright (c) 2017-2022, Arm Limited. All rights reserved.*