doc: Reformat platform port documents

The platform port documents are not very standardised right now and
they don't integrate properly into the document tree so:

1) Make sure each port has a proper name and title (incl. owner)
2) Correct use of headings, subheadings, etc in each port
3) Resolve any naming conflicts between documents

Change-Id: I4c2da6f57172b7f2af3512e766ae9ce3b840b50f
Signed-off-by: Paul Beesley <paul.beesley@arm.com>
diff --git a/docs/plat/meson-gxl.rst b/docs/plat/meson-gxl.rst
index feac2dd..3c39c9d 100644
--- a/docs/plat/meson-gxl.rst
+++ b/docs/plat/meson-gxl.rst
@@ -1,5 +1,5 @@
-Trusted Firmware-A for Amlogic Meson S905x (GXL)
-================================================
+Amlogic Meson S905x (GXL)
+=========================
 
 The Amlogic Meson S905x is a SoC with a quad core Arm Cortex-A53 running at
 1.5Ghz. It also contains a Cortex-M3 used as SCP.