Refresh: Remove all benchmarking code

[jeremyfowers]

The maintainers of TurnkeyML have decided that this project should be focused on toolflows (i.e., compilation), and not on benchmarking. We will remove all benchmarking code from this repository unless there is any objection from the community.

If the community does want to keep benchmarking in this repo, please comment on this issue and we will figure out a compromise.