[media] rc-core: add trailing silence in rc-loopback tx

If an IR command is sent (using the LIRC userspace) to rc-loopback
which doesn't include a trailing space, the result is that the message
won't be completely decoded. In addition, "leftovers" from a previous
transmission can be left until the next one. Fix this by faking a long
silence after the end of TX data.
Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/rc/rc-loopback.c

@@ -146,6 +146,12 @@ static int loop_tx_ir(struct rc_dev *dev, int *txbuf, u32 n)
 		if (rawir.duration)
 			ir_raw_event_store_with_filter(dev, &rawir);
 	}
+
+	/* Fake a silence long enough to cause us to go idle */
+	rawir.pulse = false;
+	rawir.duration = dev->timeout;
+	ir_raw_event_store_with_filter(dev, &rawir);
+
 	ir_raw_event_handle(dev);
 
 out: