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

[Angel Pons (Code Review)]

Attention is currently required from: Julius Werner, Moritz Fischer.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50887 )

Change subject: soc/rockchip/rk3399/sdram: Use rank_mask in CA training
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Patch Set 1: Code-Review+1

(1 comment)

File src/soc/rockchip/rk3399/sdram.c:

https://review.coreboot.org/c/coreboot/+/50887/comment/40a8da53_fb470abb 
PS1, Line 629: 		rank_mask = (rank == 1) ? 0x1 : 0x3;
Does `rank` here mean `number of ranks`?