[media] lirc_dev: return POLLHUP and POLLERR when device is gone

Most drivers return both values when the device is gone.
Signed-off-by: NDavid Härdeman <david@hardeman.nu>
Signed-off-by: NSean Young <sean@mess.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/rc/lirc_dev.c

@@ -372,7 +372,7 @@ unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait)
 	}
 
 	if (!ir->attached)
-		return POLLERR;
+		return POLLHUP | POLLERR;
 
 	if (ir->buf) {
 		poll_wait(file, &ir->buf->wait_poll, wait);