Extend CI/CD to build firmware for all hardware

[glopesdev]

Using an external Makefile to build the firmware will ensure that the same steps are used when building the firmware
either from Atmel Studio or through the CI pipeline.

Firmware build step on GitHub Actions workflow uses the same AVR-GCC toolchain version to ensure reproducible
builds. Version numbers are defined using conditional preprocessor flags which are then set via Makefile variants to allow building for different hardware targets.

[glopesdev]

Feedback from SRM:

• Firmware build artifacts should be tagged with a suffix that clearly indicates they are preview builds, e.g. commit hash. Toolkit firmware update tool may need to take this suffix into account when parsing file names.
  • Alternatives:
    • commit hash (preferred, could be leveraged to inject in the tag release): Behavior-fw3.3-harp1.15-hw2.0-ass0-commitsha.hex
    • ci build counter (could be a temporary fix, since this is a numeric counter it would be compatible with the current format regex for firmware "previews"): Behavior-fw3.3-harp1.15-hw2.0-ass0-preview21.hex
    • both: Behavior-fw3.3-harp1.15-hw2.0-ass0-commitsha-ci21.hex
• In the future we will also inject the device sha in the firmware build, but not right now.
• Review naming convention for firmware .hex files. Make a proposal for this that also takes into account the pico firmware release names, e.g. .uf2 files.

[glopesdev]

@bruno-f-cruz Added the preview suffix for all CI firmware artifacts. Conditional removal of the suffix for releases will be resolved on the next PR which expands this workflow to upload release assets.

As discussed we will temporarily use the preview suffix with the workflow run number until we review the firmware file naming conventions in the protocol.