drm/bridge: analogix_dp: Formalize the struct analogix_dp_device

drm/bridge: analogix_dp: Formalize the struct analogix_dp_device

Use the tap instead of the space for &analogix_dp_device.aux and
&analogix_dp_device.force_hpd.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Tested-by: Heiko Stuebner <heiko@sntech.de> (on rk3588)
Link: https://patch.msgid.link/20251217093321.3108939-3-damon.ding@rock-chips.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>