[bootlin/training-materials] 7dedcf: Buildroot lab: fix kernel headers version

[Michael Opdenacker]

  Branch: refs/heads/master
  Home:   https://github.com/bootlin/training-materials
  Commit: 7dedcf5b13a7c3dd89be9b1c554d3fa6da204d9a
      https://github.com/bootlin/training-materials/commit/7dedcf5b13a7c3dd89be9b1c554d3fa6da204d9a
  Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
  Date:   2022-04-13 (Wed, 13 Apr 2022)

  Changed paths:
    M labs/sysdev-buildroot/sysdev-buildroot.tex

  Log Message:
  -----------
  Buildroot lab: fix kernel headers version

Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>