rockchip: spl: veyron speedy boots from SPI

Apparently speedy was forgotten from this list of veyron devices.

Fixes: 49105fb7 ("rockchip: add common spl board file")
Signed-off-by: Urja Rannikko <urjaman@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>