drm/hisilicon/hibmc: add dp module in hibmc

drm/hisilicon/hibmc: add dp module in hibmc

To support DP interface displaying in hibmc driver. Add
a encoder and connector for DP modual. The HPD function
and get_edid function will be add in next series, so temporarily
using 1024x768 as default in hibmc_dp_connector_get_modes()

Signed-off-by: Baihan Li <libaihan@huawei.com>
Signed-off-by: Yongbang Shi <shiyongbang@huawei.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250103093824.1963816-6-shiyongbang@huawei.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>