Change in coreboot[master]: mb/clevo/tgl-u: Add Clevo NV41 Tiger Lake laptop support

[Michael Niewöhner (Code Review)]

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

Change subject: mb/clevo/tgl-u: Add Clevo NV41 Tiger Lake laptop support
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Patch Set 5:

(3 comments)

File src/mainboard/clevo/tgl-u/bootblock.c:

https://review.coreboot.org/c/coreboot/+/62498/comment/f97fcec0_3567de21 
PS1, Line 16: 	if (onoff) {
            : 		gpio_set(DGPU_RST_N, 0);
            : 		mdelay(4);
            : 		gpio_set(DGPU_PWR_EN, 1);
            : 		mdelay(4);
            : 		gpio_set(DGPU_RST_N, 1);
            : 	} else {
            : 		gpio_set(DGPU_RST_N, 0);
            : 		mdelay(4);
            : 		gpio_set(DGPU_PWR_EN, 0);
> Also, no polling for PWROK/PG to assert before releasing dGPU reset?

the gpios might be mb specific; we still have APIs to handle that in a generic way

File src/mainboard/clevo/tgl-u/variants/nv4x/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/62498/comment/fea18805_5bddf0d1 
PS3, Line 4: 	# TODO: Check if this is correct
it's not wrong, but the fans should be powerful enough to handle way more power

https://review.coreboot.org/c/coreboot/+/62498/comment/6e233411_ff13aab3 
PS3, Line 42: 			register "HybridStorageMode" = "0"
not needed, 0 is the default