Juno: add basic support for dynamic config

Add the disable_auth dynamic parameter, that allows to disable the
authentication when TBBR is enabled. This parameter is for development
only.

Change-Id: Ic24ad16738517f7e07c4f506dcf69a1ae8df7d2d
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
2 files changed