[U-Boot] [U-Boot, 33/36] rockchip: dts: rk3399-firefly: enable uart2 in spl

[Philipp Tomsich]

> pre-loader console in SPL needs UART.
> 
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> ---
> 
>  arch/arm/dts/rk3399-firefly.dts | 1 +
>  1 file changed, 1 insertion(+)
> 

Acked-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>