drm/msm/dpu: Add support for SM8350

Add compatibles string, "qcom,sm8350-dpu", for the display processing unit
used on Qualcomm SM8350 platform.

Signed-off-by: Robert Foss <robert.foss@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/516342/
Link: https://lore.kernel.org/r/20221230153554.105856-5-robert.foss@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>