drm/bridge: analogix_dp: Add support for &drm_dp_aux.wait_hpd_asserted()

Add analogix_dpaux_wait_hpd_asserted() to help confirm the HPD state
before doing AUX transfers.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20250310104114.2608063-8-damon.ding@rock-chips.com


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>