rdn2cfg2/run_model: route uart logs via secure/non-secure uart

Use secure and non-secure uarts in CSS instead of the uarts in SOC.
TF-A boot, runtime and Standalone MM logs would be routed via
css[0/1/2/3].pl011_s_uart_ap (secure port). UEFI and OS logs would be
routed via css[0/1/2/3].pl011_ns_uart_ap (non-secure port)

Additionally, as TF-A and MM logs would be routed via the same UART
port, remove unused model parameters that are used for configuring uart
port for capturing Standalone MM logs.

Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
Change-Id: I0e8fa6c1b8e143cf316471a719c668b39734ef11