Resolve documentation build errors

Eliminated all the warnings and errors in the documentations.

Signed-off-by: Gabor Toth <gabor.toth2@arm.com>
Change-Id: I355b0db832e62d7eb4f0968c309e547ae7a51dc3
diff --git a/docs/conf.py b/docs/conf.py
index feeca38..3bdd93e 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -91,7 +91,7 @@
 
 #Add custom css for HTML. Used to allow full page width rendering
 def setup(app):
-    app.add_stylesheet('css/custom.css')
+    app.add_css_file('css/custom.css')
 
 
 # -- Options for autosectionlabel --------------------------------------------
diff --git a/docs/environments/secure-partitions/spm/optee/userspace-programs-on-fvp.rst b/docs/environments/secure-partitions/spm/optee/userspace-programs-on-fvp.rst
index e364839..56df3a3 100644
--- a/docs/environments/secure-partitions/spm/optee/userspace-programs-on-fvp.rst
+++ b/docs/environments/secure-partitions/spm/optee/userspace-programs-on-fvp.rst
@@ -29,7 +29,7 @@
 the makefiles in the ``op-tee/build`` repository.
 
 To build all such binaries build the ``ffa-test-all`` target. For available targets please refer to
-fvp-psa-sp.mk_. As an example to build the ``ts-service-test`` application execute the following
+`fvp-psa-sp.mk`. As an example to build the ``ts-service-test`` application execute the following
 commands from the root of the workspace::
 
     make -C build ffa-ts-service-test
@@ -143,7 +143,7 @@
 
 --------------
 
-.. _fvp-psa-sp.mk :https://github.com/OP-TEE/build/blob/master/fvp-psa-sp.mk
+.. _fvp-psa-sp.mk: https://github.com/OP-TEE/build/blob/master/fvp-psa-sp.mk
 
 *Copyright (c) 2020-2022, Arm Limited and Contributors. All rights reserved.*
 
diff --git a/docs/project/coding-guidelines.rst b/docs/project/coding-guidelines.rst
index 5b5607a..4251393 100644
--- a/docs/project/coding-guidelines.rst
+++ b/docs/project/coding-guidelines.rst
@@ -38,8 +38,8 @@
     * SPDX-License-Identifier: BSD-3-Clause
     */
 
-Boring stuff is not for smart people and the project uses the `Uncrustify`_ code beautifier to easy formatting the
-source. (See :download:`../../.uncrustify.cfg`)
+Boring stuff is not for smart people and the project uses the `Clang-Format`_ code beautifier to easy formatting the
+source. (See :download:`../../.clang-format`)
 
 CMake Rules
 -----------
@@ -80,7 +80,7 @@
 .. _`snake_case`: https://en.wikipedia.org/wiki/Snake_case
 .. _`CMake Documentation`: https://github.com/Kitware/CMake/blob/master/Help/dev/documentation.rst
 .. _`EditorConfig`: https://editorconfig.org/
-.. _`Uncrustify`: https://github.com/uncrustify/uncrustify
+.. _`Clang-Format`: https://clang.llvm.org/docs/ClangFormat.html
 
 *Copyright (c) 2020-2022, Arm Limited and Contributors. All rights reserved.*