V4L/DVB: drivers/media/video: Use available error codes

Error codes are stored in rc, but the return value is always 0.  Return rc
instead.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
local idexpression x;
constant C;
@@

if (...) { ...
  x = -C
  ... when != x
(
  return <+...x...+>;
|
  return NULL;
|
  return;
|
* return ...;
)
}
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/zr364xx.c

@@ -572,7 +572,7 @@ static int zr364xx_got_frame(struct zr364xx_camera *cam, int jpgsize)
 	DBG("wakeup [buf/i] [%p/%d]\n", buf, buf->vb.i);
 unlock:
 	spin_unlock_irqrestore(&cam->slock, flags);
-	return 0;
+	return rc;
 }
 
 /* this function moves the usb stream read pipe data