ARM: dts: msm: add display related SPMI address

Add SPMI reference node along with the display related
SPMI address. This will be used during the trusted-ui
usecase where the VMs uses SPMI api to get the physical
address, which will be lent/validated during the usecase.

Change-Id: Ic3173410790443e87c0584681ec1f0c160fc04a2