doc: Remove per-page contents lists

These are no longer needed as there will always be a table of contents
rendered to the left of every page.

Some of these lists can be quite long and, when opening a page, the
reader sees nothing but a huge list of contents! After this patch,
the document contents are front-and-centre and the contents are
nicely rendered in the sidebar without duplication.

Change-Id: I444754d548ec91d00f2b04e861de8dde8856aa62
Signed-off-by: Paul Beesley <paul.beesley@arm.com>
diff --git a/docs/index.rst b/docs/index.rst
index b0348f1..f23b948 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -3,7 +3,7 @@
 
 .. toctree::
    :maxdepth: 1
-   :caption: Contents
+   :hidden:
 
    Home<self>
    getting_started/index
@@ -18,6 +18,9 @@
    maintainers
    license
 
+.. contents:: On This Page
+    :depth: 3
+
 Trusted Firmware-A (TF-A) provides a reference implementation of secure world
 software for `Armv7-A and Armv8-A`_, including a `Secure Monitor`_ executing
 at Exception Level 3 (EL3). It implements various Arm interface standards,