drm/bridge: lt8912b: Register and attach our DSI device at probe

In order to avoid any probe ordering issue, the best practice is to move
the secondary MIPI-DSI device registration and attachment to the
MIPI-DSI host at probe time. Let's do this.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20211025151536.1048186-7-maxime@cerno.tech

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

@@ -544,10 +544,6 @@ static int lt8912_bridge_attach(struct drm_bridge *bridge,
 	if (ret)
 		goto error;
 
-	ret = lt8912_attach_dsi(lt);
-	if (ret)
-		goto error;
-
 	lt->is_attached = true;
 
 	return 0;
@@ -706,8 +702,15 @@ static int lt8912_probe(struct i2c_client *client,
 
 	drm_bridge_add(&lt->bridge);
 
+	ret = lt8912_attach_dsi(lt);
+	if (ret)
+		goto err_attach;
+
 	return 0;
 
+err_attach:
+	drm_bridge_remove(&lt->bridge);
+	lt8912_free_i2c(lt);
 err_i2c:
 	lt8912_put_dt(lt);
 err_dt_parse: