ARM: dts: msm: Update kgsl clk lists for SM6150 GPU

Remove GCC_GPU_SNOC_DVM_GFX_CLK and GPU_CFG_AHB_CLK clocks from gpu,
rgmu and kgsl iommu clock lists since these are not required.

Change-Id: I120e37339d10067143067232034d3935c1adb2ac
Signed-off-by: Akhil P Oommen <akhilpo@codeaurora.org>