drm/msm/dpu: index dpu_kms->hw_vbif using vbif_idx

drm/msm/dpu: index dpu_kms->hw_vbif using vbif_idx

Remove loops over hw_vbif. Instead always VBIF's idx as an index in the
array. This fixes an error in dpu_kms_hw_init(), where we fill
dpu_kms->hw_vbif[i], but check for an error pointer at
dpu_kms->hw_vbif[vbif_idx].

Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/489569/
Link: https://lore.kernel.org/r/20220615125703.24647-1-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>