ci: Update base image to use bullseye and llvmpipe as the host driver
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
Edited by Gert Wollny