Docs: Fix broken PDF version of the User guide

- Limit FWU design document content table depth to comply with Latex
- Reduce the Design Documents content table to titles only

Signed-off-by: Anton Komlev <anton.komlev@arm.com>
Change-Id: Ia9df1b2a896f7a662bdd84e671fc091a227e25e6
diff --git a/docs/CMakeLists.txt b/docs/CMakeLists.txt
index 352f415..cf3e364 100644
--- a/docs/CMakeLists.txt
+++ b/docs/CMakeLists.txt
@@ -40,22 +40,13 @@
 )
 add_dependencies(docs tfm_docs_userguide_html)
 
-add_custom_command(OUTPUT "${SPHINXCFG_OUTPUT_PATH}/latex/TF-M.tex"
-    OUTPUT "${SPHINXCFG_OUTPUT_PATH}/latex/"
-    COMMAND "${SPHINX_EXECUTABLE}" -b latex "${SPHINXCFG_SOURCE_PATH}" "${SPHINXCFG_OUTPUT_PATH}/latex"
-    WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
-    DEPENDS tfm_docs_sphinx_cfg
+add_custom_target(tfm_docs_userguide_pdf ALL
+    COMMAND "${SPHINX_EXECUTABLE}" -W -b latex -j auto -c ${SPHINXCFG_CONFIG_PATH} ${SPHINXCFG_SOURCE_PATH} "${SPHINXCFG_OUTPUT_PATH}/latex"
+    COMMAND ${PDFLATEX_COMPILER} -output-directory "${SPHINXCFG_OUTPUT_PATH}/latex" TF-M.tex
+    COMMAND ${CMAKE_COMMAND} -E copy "${SPHINXCFG_OUTPUT_PATH}/latex/TF-M.pdf" "${SPHINXCFG_OUTPUT_PATH}/tf-m_user_guide.pdf"
+    WORKING_DIRECTORY ${SPHINXCFG_SOURCE_PATH}
     DEPENDS ${SPHINXCFG_DOC_FILES}
 )
-add_custom_command(OUTPUT "${SPHINXCFG_OUTPUT_PATH}/latex/TF-M.pdf"
-    COMMAND ${PDFLATEX_COMPILER} TF-M.tex
-    COMMAND ${CMAKE_COMMAND} -E copy TF-M.tex ${SPHINXCFG_OUTPUT_PATH}/tf-m_user_guide.pdf
-    WORKING_DIRECTORY ${SPHINXCFG_OUTPUT_PATH}/latex/
-    DEPENDS "${SPHINXCFG_OUTPUT_PATH}/latex/TF-M.tex"
-)
-add_custom_target(tfm_docs_userguide_pdf
-    DEPENDS "${SPHINXCFG_OUTPUT_PATH}/latex/TF-M.pdf"
-)
 add_dependencies(docs tfm_docs_userguide_pdf)
 
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