[U-Boot] [U-Boot, 2/8] rockchip: rk322x: sdram: use udelay instead of rockchip_udelay

[Philipp Tomsich]

> Use system api for udelay instead of vendor defined api,
> and rockchip_udelay() will be removed.
> 
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> ---
> 
>  drivers/ram/rockchip/sdram_rk322x.c | 29 ++++++++++++++---------------
>  1 file changed, 14 insertions(+), 15 deletions(-)
> 

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