[U-Boot] [U-Boot, 5/6] net: gmac_rockchip: Use the proerty of "clock_in_out" to set mac clock

[Philipp Tomsich]

> If the mac clock if from the external IO, set clock rate with 0;
> If the mac clock if from the internal divider pll, set 50M for
> rmii mode and set 125M for rgmii.
> 
> Signed-off-by: David Wu <david.wu at rock-chips.com>
> Acked-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> ---
> 
>  drivers/net/gmac_rockchip.c | 23 +++++++++++++++++++----
>  1 file changed, 19 insertions(+), 4 deletions(-)
> 

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