[S] Change in coreboot[main]: mb/google/nissa/var/rull: Add Elan touchscreen

[Rui Zhou (Code Review)]

Attention is currently required from: Dinesh Gehlot, Eric Lai, Jayvik Desai, Kapil Porwal, Nick Vaccaro, Subrata Banik.

Rui Zhou has posted comments on this change by Rui Zhou. ( https://review.coreboot.org/c/coreboot/+/85015?usp=email )

Change subject: mb/google/nissa/var/rull: Add Elan touchscreen
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Patch Set 6:

(1 comment)

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

https://review.coreboot.org/c/coreboot/+/85015/comment/c0abd989_af439f0a?usp... :
PS3, Line 232: 280
> please check this value can be shorten or not.

I referred to all the coreboot commits. Regarding the elan touchscreen of "hid=9004", the ```stop_delay_ms``` is set to 280 or 150. Here I changed it to 150ms. If it affects the function or suspend/resume, I will readjust it later.