Ensure the licenses are correctly placed and complete.

Issue Background

including the licenses is generally a manual issues where it is easy to forget something or make mistakes.

Issue description

Follow the Including License Information Guide now included in the OpenChain project. Follow these ba­sic steps

1. Add the li­cense to in­di­vid­u­al source files
2. In­clude the full hu­man read­able ver­sion(s) in your repos­i­to­ry
3. Cre­ate a SPDX file
4. (Op­tion­al) In­clude li­cense in­fo in the pack­age de­scrip­tion
5. Put it in your con­trib­u­tor de­scrip­tion
   • Add to the wiki, in the "how to contribute" section of the landing page, a reference to the Including License Information documet in order to commit a change.

Acceptance criteria

• Add the li­cense to in­di­vid­u­al source files: describe the process followed in the comments.
• In­clude the full hu­man read­able ver­sion(s) in your repository
• Cre­ate the SPDX files for each repo:
  • board-at-desk-single-dev repository
  • kernelci-backend
  • kernelci-backend-config
  • kernelci-frontend
  • kernelci-frontend-config
  • kernelci-build
• Put it in your con­trib­u­tor de­scrip­tion: add in the how to contribute section of the wiki a note about adding the license and follow this process, referencing the guide. Link