drm/bridge: synopsys: dw-dp: Check return value of devm_drm_bridge_add() in dw_dp_bind()

Return the value of devm_drm_bridge_add() in order to propagate the
error properly, if it fails due to resource allocation failure or bridge
registration failure.

This ensures that the bind function fails safely rather than proceeding
with a potentially incomplete bridge setup.

Fixes: b726970 ("drm/bridge: synopsys: dw-dp: add bridge before attaching")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Reviewed-by: Andy Yan <andyshrk@163.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Link: https://patch.msgid.link/20260206040621.4095517-1-nichen@iscas.ac.cn
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

Author: Chen Ni

drivers/gpu/drm/bridge/synopsys/dw-dp.c

@@ -2049,7 +2049,9 @@ struct dw_dp *dw_dp_bind(struct device *dev, struct drm_encoder *encoder,
 	bridge->type = DRM_MODE_CONNECTOR_DisplayPort;
 	bridge->ycbcr_420_allowed = true;
 
-	devm_drm_bridge_add(dev, bridge);
+	ret = devm_drm_bridge_add(dev, bridge);
+	if (ret)
+		return ERR_PTR(ret);
 
 	dp->aux.dev = dev;
 	dp->aux.drm_dev = encoder->dev;