ARM: dts: qcom: Update bw table and iommu properties of msm8917 GPU

Following changes are made:

1. Update gpu_bw_tbl in terms of operating point for gpubw.
2. GPU takes care of creating desired dma mapping by itself,
   so disable iommu-dma.
3. Remove unsupported property "qcom,protect".

Change-Id: Ic4330537883d5f639d681cfe7fb63019fb5c26bb