Docs: Support Sphinx SVG to PDF

Add support Sphinx SVG to PDF.

Signed-off-by: Summer Qin <summer.qin@arm.com>
Change-Id: Ie109c6e34c2c55c8c4049024b63148c358a74fb6
diff --git a/docs/conf.py.in b/docs/conf.py.in
index f3739be..99b2fcb 100644
--- a/docs/conf.py.in
+++ b/docs/conf.py.in
@@ -49,7 +49,8 @@
     'sphinx.ext.imgmath',
     'm2r', #Support markdown files. Needed for external code.
     'sphinx.ext.autosectionlabel', #Make sphinx generate a label for each section
-    'sphinxcontrib.plantuml' #Add support for PlantUML drawings
+    'sphinxcontrib.plantuml', #Add support for PlantUML drawings
+    'sphinxcontrib.rsvgconverter' #Add support for PlantUML drawings
 ]
 
 #Location of PlantUML