drm/msm/dpu: replace VBIF-related array with bare pointers

drm/msm/dpu: replace VBIF-related array with bare pointers

As we no longer have multiple VBIF instances, it doesn't make sense to
keep VBIF data as arrays. Drop the extra wrapping and keep only a single
instance of each of the structures.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/707776/
Link: https://lore.kernel.org/r/20260227-drop-vbif-nrt-v1-3-2b97d0438182@oss.qualcomm.com