[U-Boot] [U-Boot, 4/8] rockchip: rk3036: 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>
> ---
> 
>  arch/arm/mach-rockchip/rk3036/sdram_rk3036.c | 19 +++++++++----------
>  1 file changed, 9 insertions(+), 10 deletions(-)
> 

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