Docs: Add AN number to supported ARM platforms list

This patch adds the relevant Application note (AN) number
to the supported ARM platforms in readme to make it more
easier to find the supported configurations.

Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Change-Id: I58bb67f8c4d6fdf59a4360134f3b153d3c7ca4f7
1 file changed