[bootlin/training-materials] 7b194f: buildroot: put stm32 stuff into common

[Clément Léger]

  Branch: refs/heads/master
  Home:   https://github.com/bootlin/training-materials
  Commit: 7b194f34091b223e941ef6a7daf91d6033c11575
      https://github.com/bootlin/training-materials/commit/7b194f34091b223e941ef6a7daf91d6033c11575
  Author: Clément Léger <clement.leger at bootlin.com>
  Date:   2022-10-13 (Thu, 13 Oct 2022)

  Changed paths:
    A common/stm32-prepare.tex
    M labs/buildroot-basic-stm32/buildroot-basic-stm32.tex

  Log Message:
  -----------
  buildroot: put stm32 stuff into common

This will be reused by the debugging labs.

Signed-off-by: Clément Léger <clement.leger at bootlin.com>