[media] tlg2300: fix checking firmware in poseidon_probe()

check_firmware() makes sure firmware is in a device.
It returns zero on success and error code otherwise.
Also it sets down_firmware flag to 1 if downloading occurs.
The only caller poseidon_probe() checks down_firmware flag and
returns 0 without any initialization if it is set.
That looks very strange, so the patch removes down_firmware argument
of check_firmware() and returns error code if check_firmware() fails
in poseidon_probe().
Not tested on real hardware.
Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/usb/tlg2300/pd-main.c

@@ -375,7 +375,7 @@ static inline void set_map_flags(struct poseidon *pd, struct usb_device *udev)
 }
 #endif
 
-static int check_firmware(struct usb_device *udev, int *down_firmware)
+static int check_firmware(struct usb_device *udev)
 {
 	void *buf;
 	int ret;
@@ -395,10 +395,8 @@ static int check_firmware(struct usb_device *udev, int *down_firmware)
 			 USB_CTRL_GET_TIMEOUT);
 	kfree(buf);
 
-	if (ret < 0) {
-		*down_firmware = 1;
+	if (ret < 0)
 		return firmware_download(udev);
-	}
 	return 0;
 }
 
@@ -411,9 +409,9 @@ static int poseidon_probe(struct usb_interface *interface,
 	int new_one = 0;
 
 	/* download firmware */
-	check_firmware(udev, &ret);
+	ret = check_firmware(udev);
 	if (ret)
-		return 0;
+		return ret;
 
 	/* Do I recovery from the hibernate ? */
 	pd = find_old_poseidon(udev);