arm64: dts: qcom: sc7280: Mark Adreno SMMU as DMA coherent

The SMMUs on sc7280 are cache-coherent. APPS_SMMU is marked as such,
mark the GPU one as well.

Fixes: 96c47197 ("arm64: dts: qcom: sc7280: Add gpu support")
Reviewed-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230926-topic-a643-v2-3-06fa3d899c0a@linaro.org


Signed-off-by: Bjorn Andersson <andersson@kernel.org>