drm/msm/dpu: rename CDM block definition

The CDM block is not limited to SC7280, but it is common to all
platforms since DPU 5.x. Rename it from sc7280_cdm to
dpu_cdm_5_x.

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/638405/
Link: https://lore.kernel.org/r/20250220-dpu-add-cdm-v2-1-77f5f0df3d9a@linaro.org