[coreboot-gerrit] [M] Change in coreboot[master]: mainboard: Add SPDX license headers to Makefiles

[Alexander Couzens (Code Review)]

Attention is currently required from: Felix Singer, Jason Nien, Jeremy Soller, Angel Pons, Martin Roth, Tim Crawford, Tarun Tuli, Martin L Roth, Damien Zammit, Subrata Banik, Maxim Polyakov, Kapil Porwal, Werner Zeh, Evgeny Zinoviev.

Alexander Couzens has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/68982 )

Change subject: mainboard: Add SPDX license headers to Makefiles
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Patch Set 2:

(1 comment)

Patchset:

PS2: 
@Martin: not sure if we already have this. It would be great if we have a linter job  which warns if someone adds a file without SPDX header.