[S] Change in coreboot[main]: mb/google/nissa/var/rull: add touchpad init config of Synaptics&PIXART

[Subrata Banik (Code Review)]

Attention is currently required from: Dinesh Gehlot, Eric Lai, Jayvik Desai, Kapil Porwal, Kyle Lin, Lei Cao, Nick Vaccaro, Rui Zhou.

Subrata Banik has posted comments on this change by Rui Zhou. ( https://review.coreboot.org/c/coreboot/+/84999?usp=email )

Change subject: mb/google/nissa/var/rull: add touchpad init config of Synaptics&PIXART
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Patch Set 6:

(1 comment)

File src/mainboard/google/brya/variants/rull/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/84999/comment/6d03cb18_c6f0ba2d?usp... :
PS4, Line 253: 			end
> adding fw_config will double the number of items in  CBI table and make it harder to maintain for factory: https://docs.google.com/spreadsheets/d/11NeXYcg2G-rFmChh2_5T65sJRSYMyPI5/edi...,  is it really mandatory for coreboot? if yes , use SSFC for 2nd source should be better

i believe it would be problematic to use SSFC inside .cb for probing the ACPI code