media: rc: ensure input/lirc device can be opened after register

Since commit cb84343fced1 ("media: lirc: do not call close() or open() on
unregistered devices") rc_open() will return -ENODEV if rcdev->registered
is false. Ensure this is set before we register the input device and the
lirc device, else we have a short window where the neither the lirc or
input device can be opened.

Fixes: cb84343fced1 ("media: lirc: do not call close() or open() on unregistered devices")

Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/rc/rc-main.c

@@ -1862,6 +1862,8 @@ int rc_register_device(struct rc_dev *dev)
 		 dev->device_name ?: "Unspecified device", path ?: "N/A");
 	kfree(path);
 
+	dev->registered = true;
+
 	if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
 		rc = rc_setup_rx_device(dev);
 		if (rc)
@@ -1881,8 +1883,6 @@ int rc_register_device(struct rc_dev *dev)
 			goto out_lirc;
 	}
 
-	dev->registered = true;
-
 	dev_dbg(&dev->dev, "Registered rc%u (driver: %s)\n", dev->minor,
 		dev->driver_name ? dev->driver_name : "unknown");