Change in coreboot[master]: mb/clevo/tgl-u: Add Clevo NV4x Tiger Lake laptop support

[Michał Kopeć (Code Review)]

Attention is currently required from: Felix Singer, Michał Żygowski, Angel Pons, Michael Niewöhner.
Michał Kopeć has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62498 )

Change subject: mb/clevo/tgl-u: Add Clevo NV4x Tiger Lake laptop support
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Patch Set 6:

(2 comments)

File src/mainboard/clevo/tgl-u/variants/nv40mz/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/62498/comment/c166943c_7a27abce 
PS6, Line 261: Pantone ROM
> I wonder what this EEPROM is used for.

Some models ship with a Pantone-validated display. I think this ROM stores the certification data, but I don't have a way to test this

File src/mainboard/clevo/tgl-u/variants/nv40mz/ramstage.c:

https://review.coreboot.org/c/coreboot/+/62498/comment/14a96780_11405fa9 
PS6, Line 9: 	 * Disable AER for the SSD slot to support S0ix with SSDs running
           : 	 * buggy firmware
           :
> any more details on this?

Samsung 980 (non-pro) SSD causes the laptop to fail to wake from s0ix standby while AER is enabled. Vendor firmware disables AER for this RP, probably for this reason, so I did the same here