drm/bridge: lt8912: Convert to drm_of_get_data_lanes_count_ep

Convert driver to use this new helper to standardize
OF "data-lanes" parsing.
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Adrien Grassein <adrien.grassein@gmail.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
To: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220524010522.528569-4-marex@denx.de

drivers/gpu/drm/bridge/lontium-lt8912b.c

@@ -607,7 +607,6 @@ static int lt8912_parse_dt(struct lt8912 *lt)
 	int ret;
 	int data_lanes;
 	struct device_node *port_node;
-	struct device_node *endpoint;
 
 	gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(gp_reset)) {
@@ -618,16 +617,12 @@ static int lt8912_parse_dt(struct lt8912 *lt)
 	}
 	lt->gp_reset = gp_reset;
 
-	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1);
-	if (!endpoint)
-		return -ENODEV;
-
-	data_lanes = of_property_count_u32_elems(endpoint, "data-lanes");
-	of_node_put(endpoint);
+	data_lanes = drm_of_get_data_lanes_count_ep(dev->of_node, 0, -1, 1, 4);
 	if (data_lanes < 0) {
 		dev_err(lt->dev, "%s: Bad data-lanes property\n", __func__);
 		return data_lanes;
 	}
+
 	lt->data_lanes = data_lanes;
 
 	lt->host_node = of_graph_get_remote_node(dev->of_node, 0, -1);