drm/dsi: Add routine to unregister a DSI device

A driver calling mipi_dsi_device_register_full() might want to remove
the device once it's done. It might also require it in an error handling
path in case something went wrong.

Create mipi_dsi_device_unregister() for this purpose and use it within
mipi_dsi_remove_device_fn() as it does the same thing.

Reviewed-by: Andrzej Hajda <[e-mail]>
Signed-off-by: Archit Taneja <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>

drivers/gpu/drm/drm_mipi_dsi.c

···
 }
 EXPORT_SYMBOL(mipi_dsi_device_register_full);
 
+/**
+ * mipi_dsi_device_unregister - unregister MIPI DSI device
+ * @dsi: DSI peripheral device
+ */
+void mipi_dsi_device_unregister(struct mipi_dsi_device *dsi)
+{
+	device_unregister(&dsi->dev);
+}
+EXPORT_SYMBOL(mipi_dsi_device_unregister);
+
 int mipi_dsi_host_register(struct mipi_dsi_host *host)
 {
 	struct device_node *node;
···
 {
 	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
 
-	device_unregister(&dsi->dev);
+	mipi_dsi_device_unregister(dsi);
 
 	return 0;
 }

include/drm/drm_mipi_dsi.h

···
 struct mipi_dsi_device *
 mipi_dsi_device_register_full(struct mipi_dsi_host *host,
 			      const struct mipi_dsi_device_info *info);
+void mipi_dsi_device_unregister(struct mipi_dsi_device *dsi);
 struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node *np);
 int mipi_dsi_attach(struct mipi_dsi_device *dsi);
 int mipi_dsi_detach(struct mipi_dsi_device *dsi);