drm/hisilicon/hibmc: add dp mode valid check

drm/hisilicon/hibmc: add dp mode valid check

If DP is connected, check the DP BW in mode_valid_ctx() to ensure
that DP's link rate supports high-resolution data transmission.

Fixes: 0ab6ea261c1f ("drm/hisilicon/hibmc: add dp module in hibmc")
Signed-off-by: Baihan Li <libaihan@huawei.com>
Signed-off-by: Yongbang Shi <shiyongbang@huawei.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Tao Tian <tiantao6@hisilicon.com>
Link: https://patch.msgid.link/20251210023759.3944834-3-shiyongbang@huawei.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>