ARM: dts: msm: Add remote debugger device configuration for SDM670

Remote Debugger driver allows a debugger running on a
host PC to communicate with a remote stub running on
peripheral subsystems.

Change-Id: I77918370e3bd89c67e6706e55979609fd674751e
Signed-off-by: Tharun Kumar Merugu <mtharu@codeaurora.org>