drm: atmel-hlcdc: add info messages

Add dev_info messages to inform the user when the display controller is
up and running.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[nicolas.ferre@atmel.com: adapt to newer driver]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Author: Boris Brezillon

drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c

@@ -786,6 +786,7 @@ static int atmel_hlcdc_dc_drm_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_unload;
 
+	dev_info(ddev->dev, "DRM device successfully registered\n");
 	return 0;
 
 err_unload: