Update the CI to use bullseye and the latest commits of mesa, CTS, piglit, and switch the host driver to llvmpipe.
- bullseye is close to become stabe, and some packages in there are required to compile current versions of mesa.
- llvmpipe gives us a way better coverage now that is supports up to GLES 3.2 and GL 4.5
- about 2000 tests regress
- about 700 tests are fixes
- around 19k more tests are now supported