Change in coreboot[master]: mb/clevo/tgl-u: add new board L14xMU

[Angel Pons (Code Review)]

Attention is currently required from: Felix Singer, Nico Huber, Michał Żygowski, Michał Kopeć, Paul Menzel, Michael Niewöhner.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59548 )

Change subject: mb/clevo/tgl-u: add new board L14xMU
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Patch Set 15: Code-Review+1

(2 comments)

File src/mainboard/clevo/tgl-u/Kconfig:

https://review.coreboot.org/c/coreboot/+/59548/comment/7f7bcf8c_7f5b4f2a 
PS13, Line 12: 	select MAINBOARD_HAS_LPC_TPM
> well, we have no means making that selectable for the user atm. […]

Ack

File src/mainboard/clevo/tgl-u/variants/l140mu/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/59548/comment/3d7572d1_454e9c9f 
PS14, Line 191: 		device ref peg on
> > why? it's a SSD slot like pcie_rp9, so grouping them makes more sense to me […]

Yeah, it's because I'd expect PEG RPs to come before PCH PCIe RPs. I don't care enough about it though.