ARM: dts: msm: Add rpmsg entry for cdsprm in sdmmagpie

cdsprm module relies on rpmsg to communicate with CDSP for CPU L3
clock frequency requests, Cx ipeak limit management and thermal
mitigation. The change constitues of rpmsg driver and dependent
configurations for CPU L3, Cx ipeak and thermal management on
sdmmagpie.

Change-Id: I3b25cbccb7cf0efc91165545ac9b3f3b2173849a
Acked-by: Sreekanth Gande <sgande@qti.qualcomm.com>
Signed-off-by: Tharun Kumar Merugu <mtharu@codeaurora.org>