Should we remove the TB directory from this project?

The OpenHW Group CORE-V projects have separate GitHub projects for design and verification. As such, the production testbench for cv32e40p is not the one in the tb directory. Given that, I recommend it be removed from this repo altogether and replaced with a pointer to the core-v-verif project.

The obvious objections to this proposal is that the testbench in cv32e40p can be used by the designers for basic sanity. This is not a good idea because it allows design updates to be made without ensuring the testbenches are kept up to date. Basic sanity means the RTL and TB are compatible and work together. This must always be true. So if a designer needs to run a sanity test (which will always be supported), they need the core-v-verif project.