rdv3r1: set telnet port for uart ports

socket0.ros0.terminal2 and socket0.ros0.terminal3 will be used for
communicating with BMC (BaseFvp). socat will be used to make the
connection. It will be convenient to have a fixed telnet port for these
uart ports rather than checking the prints from the fvp execution logs
to find the telnet port number to establish the socat communication.

Signed-off-by: Davidson K <davidson.kumaresan@arm.com>