Draft: Efforts to support latest tflite-micro

[PhilippvK]

For reference here is a summary of my past efforts to get TFLMC running with current tflite-micro. This heavily depends on @andrewstevens-infineon works over the past two years and should mainly be for reference and to compare with the approach used in #70.

I've tried to strip down the changes to the bare essentials, removing all IFX-related boilerplate code as well as the history as I am not sure if these should be available upstream.

On top of that I fixed the Cake configuration to build the custom tflite-micro lib (no need to use the tflite-micro Makefile) anymore.

To use this codebase, a patched tflite-micro codebase is required. See my branch feature/tflmc_support2 (Diff) for reference. It builds up on upstream commit 17b795d4233844144624df04c11ca1d967e81033 and the impressive work of @andrewstevens-infineon. Again, I cut the changes down to only the minimum required for the preinterpretation (adding hooks to records allocations etc.)

I do not want to merge this as-is. The main work was done by the people around @andrewstevens-infineon. My contribution was "just" digging through all the changes and pick/cleanup them to generate a meaningful diff as shown below.