Fix Broadcom Stingray platform documentation

 - Include the platform documentation in the table of contents.

 - Add a title for the document. Without this, the platform
   documentation was listed under a 'Description' title on page
   https://trustedfirmware-a.readthedocs.io/en/latest/plat/index.html



 - Change TF-A git repository URL to point to tf.org (rather than the
   deprecated read-only mirror on Github).

 - Fix the restructuredText syntax for the FIP command line. It was
   not displayed at all on the rendered version.

Change-Id: I7a0f062bcf8e0dfc65e8f8bdd6775c497a47e619
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>

docs/plat/brcm-stingray.rst

+Broadcom Stingray
+=================
+
 Description
-===========
+-----------
 Broadcom's Stingray(BCM958742t) is a multi-core processor with 8 Cortex-A72 cores.
 Trusted Firmware-A (TF-A) is used to implement secure world firmware, supporting
-BL2 and BL31 for Broadcom Stingray SoCs
+BL2 and BL31 for Broadcom Stingray SoCs.
 
 On Poweron, Boot ROM will load bl2 image and Bl2 will initialize the hardware,
 then loads bl31 and bl33 into DDR and boots to bl33.
 
 Boot Sequence
-=============
+-------------
 
 Bootrom --> TF-A BL2 --> TF-A BL31 --> BL33(u-boot)
 
 Code Locations
---------------
+~~~~~~~~~~~~~~
 -  Trusted Firmware-A:
-   `link <https://github.com/ARM-software/arm-trusted-firmware>`__
+   `link <https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/>`__
 
 How to build
-============
+------------
 
 Build Procedure
----------------
+~~~~~~~~~~~~~~~
 
 -  Prepare AARCH64 toolchain.
 
@@ -31,10 +34,10 @@ Build Procedure
 
    Build fip:
 
-   .. code::shell
+   .. code:: shell
 
        make CROSS_COMPILE=aarch64-linux-gnu- PLAT=stingray BOARD_CFG=bcm958742t all fip BL33=u-boot.bin
 
 Deploy TF-A Images
------------------
+~~~~~~~~~~~~~~~~~~
 The u-boot will be upstreamed soon, this doc will be updated once they are ready, and the link will be posted.

docs/plat/index.rst

@@ -37,6 +37,7 @@ Platform Ports
    ti-k3
    xilinx-versal
    xilinx-zynqmp
+   brcm-stingray
 
 This section provides a list of supported upstream *platform ports* and the
 documentation associated with them.