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>

docs/getting_started/user-guide.rst

 User Guide
 ==========
 
-.. contents::
-
 This document describes how to build Trusted Firmware-A (TF-A) and run it with a
 tested set of other software components using defined configurations on the Juno
 Arm development platform and Arm Fixed Virtual Platform (FVP) models. It is

docs/index.rst

@@ -3,7 +3,7 @@ Trusted Firmware-A Documentation
 
 .. toctree::
    :maxdepth: 1
-   :caption: Contents
+   :hidden:
 
    Home<self>
    getting_started/index
@@ -18,6 +18,9 @@ Trusted Firmware-A Documentation
    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,

docs/plat/rpi3.rst

 Raspberry Pi 3
 ==============
 
-.. contents::
-
 The `Raspberry Pi 3`_ is an inexpensive single-board computer that contains four
 Arm Cortex-A53 cores.
 

docs/process/coding-guidelines.rst

 Coding Style & Guidelines
 =========================
 
-.. contents::
-
 The following sections contain TF coding guidelines. They are continually
 evolving and should not be considered "set in stone". Feel free to question them
 and provide feedback.

docs/process/platform-compatibility-policy.rst

 Platform Compatibility Policy
 =============================
 
-
-
-
-.. contents::
-
---------------
-
 Introduction
 ------------
 

docs/process/release-information.rst

 Release Processes
 =================
 
-.. contents::
-
---------------
-
 Project Release Cadence
 -----------------------