[XL] Change in coreboot[main]: mb/lenovo: Add ThinkCentre M920q (Cannon Lake)

[Michał Kopeć (Code Review)]

Attention is currently required from: Alexander Couzens, Maciej Pijanowski, Paul Menzel.

Michał Kopeć has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80609?usp=email )

Change subject: mb/lenovo: Add ThinkCentre M920q (Cannon Lake)
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Patch Set 6:

(3 comments)

File src/mainboard/lenovo/m920q/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/80609/comment/3e147e99_32e30d78 :
PS6, Line 58: 		# not populated. Probably enabled on some variants only.
Seems to be populated on the M920x variant.

File src/mainboard/lenovo/m920q/romstage.c:

https://review.coreboot.org/c/coreboot/+/80609/comment/77151dc4_b5abb8a9 :
PS6, Line 13: 	.spd[0] = {
Platform only has 2 DIMMs

https://review.coreboot.org/c/coreboot/+/80609/comment/3271581c_7d6c1d68 :
PS6, Line 33: 	/* Rcomp target values for CFL-S, DDR4 and 2 DIMMs per channel */
There's 1 DIMM per channel here