Change in coreboot[master]: soc/rockchip/rk3399/sdram: Use rank_mask in CA training

[Moritz Fischer (Code Review)]

Attention is currently required from: Julius Werner.
Hello build bot (Jenkins), Angel Pons, Julius Werner,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/50887

to look at the new patch set (#3).

Change subject: soc/rockchip/rk3399/sdram: Use rank_mask in CA training
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soc/rockchip/rk3399/sdram: Use rank_mask in CA training

Add rank_mask based on the rank number and iterate based on that rather
than iterating all values.

Note: LPDDR4 uses a different rank mask.

Ported from u-boot.

Signed-off-by: Moritz Fischer 
Change-Id: I85f449af9f946ad677808800cdbe59e2001202c3
---
M src/soc/rockchip/rk3399/sdram.c
1 file changed, 12 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/87/50887/3