[L] Change in coreboot[main]: mb/lenovo: Add ThinkCentre M900 (Skylake/LGA 1151)

[Angel Pons (Code Review)]

Attention is currently required from: Nicholas Chin.

Angel Pons has posted comments on this change by Nicholas Chin. ( https://review.coreboot.org/c/coreboot/+/74187?usp=email )

Change subject: mb/lenovo: Add ThinkCentre M900 (Skylake/LGA 1151)
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Patch Set 10:

(3 comments)

File src/mainboard/lenovo/m900/cmos.layout:

https://review.coreboot.org/c/coreboot/+/74187/comment/67b29e4d_32db5a32?usp... :
PS10, Line 21: 400	1	e	2	hyper_threading
Doesn't have a default

File src/mainboard/lenovo/m900/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/74187/comment/6a34ac9a_3006f5fb?usp... :
PS10, Line 42: 			register "PrimaryDisplay" = "Display_PEG"
Out of curiosity, why?

https://review.coreboot.org/c/coreboot/+/74187/comment/113e4607_5438e6f8?usp... :
PS10, Line 122: register "gen1_dec" = "0x00fc0201"
              : 			register "gen2_dec" = "0x003c0a01"
              : 			register "gen3_dec" = "0x00040069"
              : 			register "gen4_dec" = "0x000c0081"
Do we know what these decode ranges are used for?