ARM: dts: msm: Add APPS RSC device bindings for sdm670

Add device bindings for the apps processor's RSC. The RSC
contains the TCS that will be used to send sleep/wake/active
requests to the RPMH blocks for the APPS processor.

Change-Id: I24327e69fac38a9ee08349a4435fc0727137a011
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>