Fix: Tooling cleanup

[dragonmux]

Detailed description

This PR fixes some compiler warnings and CI complaints that had crept in. This includes a clang-tidy lint, a duplicated decl warning, and the clang-format oops that crept in via PR #1807.

These fixes are preparation for the STM32H7 support fix branch.

Your checklist for this pull request

• [x] I've read the Code of Conduct
• [x] I've read the guidelines for contributing to this repository
• [x] It builds for hardware native (see Building the firmware)
• [x] It builds as BMDA (see Building the BMDA)
• [x] I've tested it to the best of my ability
• [x] My commit messages provide a useful short description of what the commits do

Closing issues