Move GitHub Pages to openhwgroup/core-v-verif

Hi @rickoco, this is a big, but simple, PR. The objective is to move the coverage reports from my fork to the openhwgroup repo. This PR will do two things:

1. Delete the old doc directory.
2. Create a new docs directory (as needed by GitHub Pages) which contains the content from the old doc directory, plus the CV32E40P coverage reports and waivers.