doc: Use proper note and warning annotations

The documentation contains plenty of notes and warnings. Enable
special rendering of these blocks by converting the note prefix
into a .. note:: annotation.

Change-Id: I34e26ca6bf313d335672ab6c2645741900338822
Signed-off-by: Paul Beesley <paul.beesley@arm.com>
diff --git a/docs/index.rst b/docs/index.rst
index b0eff61..6f6cfdf 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -153,7 +153,8 @@
 Arm FVPs without shifted affinities, and that do not support threaded CPU cores
 (64-bit host machine only).
 
-The FVP models used are Version 11.5 Build 33, unless otherwise stated.
+.. note::
+   The FVP models used are Version 11.5 Build 33, unless otherwise stated.
 
 -  ``FVP_Base_AEMv8A-AEMv8A``
 -  ``FVP_Base_AEMv8A-AEMv8A-AEMv8A-AEMv8A-CCN502``
@@ -190,7 +191,8 @@
 -  ``FVP_Base_AEMv8A-AEMv8A``
 -  ``FVP_Base_Cortex-A32x4``
 
-NOTE: The ``FVP_Base_RevC-2xAEMv8A`` FVP only supports shifted affinities.
+.. note::
+   The ``FVP_Base_RevC-2xAEMv8A`` FVP only supports shifted affinities.
 
 The Foundation FVP can be downloaded free of charge. The Base FVPs can be
 licensed from Arm. See the `Arm FVP website`_.