feat(sgi): enable secure uart for rdv1 platform

Add new model parameter to enable secure uart for rdv1 platform.
Additionally, update the platform's run-config to search the right
uart port port for expect message.

Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
Change-Id: I4b7e476b89b4e3d4444dee1df8a0a605211b74c1
2 files changed