drm/msm/dsi: Use the new regulator bulk feature to specify the load

As of commit 6eabfc01 ("regulator: core: Allow specifying an
initial load w/ the bulk API") we can now specify the initial load in
the bulk data rather than having to manually call regulator_set_load()
on each regulator. Let's use it.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/496319/
Link: https://lore.kernel.org/r/20220804073608.v4.4.I7b3c72949883846badb073cfeae985c55239da1d@changeid


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>