GPU-DRM-OMAP: Delete unnecessary checks before two function calls

The following functions test whether their argument is NULL and then
return immediately.
* backlight_device_unregister
* drm_gem_object_unreference_unlocked

Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/72ff4670-4f3d-c7ed-4f37-e49f2bbc7aba@users.sourceforge.net

drivers/gpu/drm/omapdrm/displays/panel-dsi-cm.c

@@ -1284,8 +1284,7 @@ static int dsicm_probe(struct platform_device *pdev)
 	return 0;
 
 err_sysfs_create:
-	if (bldev != NULL)
-		backlight_device_unregister(bldev);
+	backlight_device_unregister(bldev);
 err_bl:
 	destroy_workqueue(ddata->workqueue);
 err_reg: