media: saa7134: fix incorrect use to determine if list is empty

'dev' will *always* be set by list_for_each_entry().
It is incorrect to assume that the iterator value will be NULL if the
list is empty.

Instead of checking the pointer it should be checked if
the list is empty.

Fixes: 79dd0c69 ("V4L: 925: saa7134 alsa is now a standalone module")
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/pci/saa7134/saa7134-alsa.c

@@ -1214,7 +1214,7 @@ static int alsa_device_exit(struct saa7134_dev *dev)
 
 static int saa7134_alsa_init(void)
 {
-	struct saa7134_dev *dev = NULL;
+	struct saa7134_dev *dev;
 
 	saa7134_dmasound_init = alsa_device_init;
 	saa7134_dmasound_exit = alsa_device_exit;
@@ -1229,7 +1229,7 @@ static int saa7134_alsa_init(void)
 			alsa_device_init(dev);
 	}
 
-	if (dev == NULL)
+	if (list_empty(&saa7134_devlist))
 		pr_info("saa7134 ALSA: no saa7134 cards found\n");
 
 	return 0;