drm/bridge: aux-hpd-bridge: fix assignment of the of_node

Perform fix similar to the one in the commit 85e444a6 ("drm/bridge:
Fix assignment of the of_node of the parent to aux bridge").

The assignment of the of_node to the aux HPD bridge needs to mark the
of_node as reused, otherwise driver core will attempt to bind resources
like pinctrl, which is going to fail as corresponding pins are already
marked as used by the parent device.
Fix that by using the device_set_of_node_from_dev() helper instead of
assigning it directly.

Fixes: e560518a ("drm/bridge: implement generic DP HPD bridge")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250608-fix-aud-hpd-bridge-v1-1-4641a6f8e381@oss.qualcomm.com