[XS] Change in coreboot[main]: mb/google/rex/var/karis: Fix touchscreen HID to ELAN9004

[Tyler Wang (Code Review)]

Attention is currently required from: David Wu, Eran Mitrani, Kapil Porwal, Paul Menzel, Subrata Banik, Tarun.

Tyler Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78266?usp=email )

Change subject: mb/google/rex/var/karis: Fix touchscreen HID to ELAN9004
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Patch Set 7:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/78266/comment/c6d1677c_b092fc47 :
PS6, Line 7: Correct touchscreen HID settings
> Please be more specific: […]

Done, thanks.

https://review.coreboot.org/c/coreboot/+/78266/comment/91c758e5_fb48a772 :
PS6, Line 8:
> Please describe the problem first. […]

The HID settings doesn't make touchscreen fail to work.
And `ELAN9004` is suggested by vendor.