arm64: dts: Add Adreno GPU and GPU smmu definitions

Add an initial node for the Adreno GPU and it's companion
SMMU. The GPU node is mostly complete except for a bare
bones power table that will be filled out more completely
later.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
[Remove mmagic clocks from GPU/smmu nodes]
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>