Instead of printing debug flags listing various CPU and GPU settings that
may or may not be used, print when we are using them. This include CPU
kernel types, OptiX debugging and CUDA and HIP adaptive compilation. BVH
type was already printed.
Remove prefix of filenames that is the same as the folder name. This used
to help when #includes were using individual files, but now they are always
relative to the cycles root directory and so the prefixes are redundant.
For patches and branches, git merge and rebase should be able to detect the
renames and move over code to the right file.
