ARM: dts: msm: add remote debugger driver dt node on 8084

The remote debugger driver allows a debugger running on a host
PC to communicate with a remote stub running on peripheral
subsystems. Add device tree entry for this driver.

Change-Id: I6ad4fb03bd660ab3babed7750a5d74045002f86d
Acked-by: Vivek Iyer <viyer@qti.qualcomm.com>
Acked-by: Mahesh Rohera <mrohera@qti.qualcomm.com>
Acked-by: Jay Jayanna <jjayanna@qti.qualcomm.com>
Signed-off-by: Aparna Das <adas@codeaurora.org>