drm/msm/dp: delete vdda regulator related functions from eDP/DP controller

Vdda regulators are related to both eDP and DP phy so that it should be
managed at eDP and DP phy driver instead of controller. This patch removes
vdda regulators related functions out of eDP/DP controller.

Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/1657038556-2231-4-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>