drm/fbdev-generic: Minimize hotplug error handling

Call drm_fb_helper_fini() in the generic-fbdev hotplug helper
to revert the effects of drm_fb_helper_init(). No full cleanup
is required.

v3:
	* fix error in commit message (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230125200415.14123-8-tzimmermann@suse.de

drivers/gpu/drm/drm_fbdev_generic.c

@@ -387,25 +387,21 @@ static int drm_fbdev_client_hotplug(struct drm_client_dev *client)
 
 	ret = drm_fb_helper_init(dev, fb_helper);
 	if (ret)
-		goto err;
+		goto err_drm_err;
 
 	if (!drm_drv_uses_atomic_modeset(dev))
 		drm_helper_disable_unused_functions(dev);
 
 	ret = drm_fb_helper_initial_config(fb_helper);
 	if (ret)
-		goto err_cleanup;
+		goto err_drm_fb_helper_fini;
 
 	return 0;
 
-err_cleanup:
-	drm_fbdev_cleanup(fb_helper);
-err:
-	fb_helper->dev = NULL;
-	fb_helper->info = NULL;
-
+err_drm_fb_helper_fini:
+	drm_fb_helper_fini(fb_helper);
+err_drm_err:
 	drm_err(dev, "fbdev: Failed to setup generic emulation (ret=%d)\n", ret);
-
 	return ret;
 }