Doc: remove the todo plugin

Remove the sphinx todo plugin as managing a task list in the
documentation is confusing and inefficient.

Change-Id: I08912ac636c098865f187cef232cfb5f314a6d4d
Signed-off-by: Gyorgy Szing <Gyorgy.Szing@arm.com>
diff --git a/docs/project/index.rst b/docs/project/index.rst
index d9bb409..91ad6bc 100644
--- a/docs/project/index.rst
+++ b/docs/project/index.rst
@@ -12,7 +12,7 @@
     license
     maintainers
     versioning_policy
-    todo
+
 
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