drm/hisilicon/hibmc: Add vga connector detect functions

Because the connected VGA connector would make driver can't get the
userspace call, adding detect_ctx in vga connector to make HPD active
userspace.

Signed-off-by: Baihan Li <libaihan@huawei.com>
Signed-off-by: Yongbang Shi <shiyongbang@huawei.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20250331074212.3370287-10-shiyongbang@huawei.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Author: mark1188-ui

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_vdac.c

@@ -60,6 +60,7 @@ static void hibmc_connector_destroy(struct drm_connector *connector)
 static const struct drm_connector_helper_funcs
 	hibmc_connector_helper_funcs = {
 	.get_modes = hibmc_connector_get_modes,
+	.detect_ctx = drm_connector_helper_detect_from_ddc,
 };
 
 static const struct drm_connector_funcs hibmc_connector_funcs = {
@@ -127,5 +128,7 @@ int hibmc_vdac_init(struct hibmc_drm_private *priv)
 
 	drm_connector_attach_encoder(connector, encoder);
 
+	connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
+
 	return 0;
 }