[ARM] Orion: use better key codes for the TS-209/TS-409 buttons

Use key codes for the buttons on the TS-209/TS-409 that make more
sense than the current values.

Signed-off-by: Martin Michlmayr <tbm@cyrius.com>
Acked-by: Byron Bradley <byron.bbradley@gmail.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>