media: omap_vout: Fix a possible null pointer dereference in omap_vout_open()

Move a debug message so that a null pointer access can not happen
for the variable "vout" in this function.

Fixes: 5c7ab634 ("V4L/DVB: V4L2: Add support for OMAP2/3 V4L2 display driver on top of DSS2")
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/omap/omap_vout.c

@@ -1004,11 +1004,12 @@ static int omap_vout_open(struct file *file)
 	struct omap_vout_device *vout = NULL;
 
 	vout = video_drvdata(file);
-	v4l2_dbg(1, debug, &vout->vid_dev->v4l2_dev, "Entering %s\n", __func__);
 
 	if (vout == NULL)
 		return -ENODEV;
 
+	v4l2_dbg(1, debug, &vout->vid_dev->v4l2_dev, "Entering %s\n", __func__);
+
 	/* for now, we only support single open */
 	if (vout->opened)
 		return -EBUSY;