DRAFT: native cpu to OCK script

[coldav]

Overview

User filter-repo to add ock to native cpu - note this is for information only, not to be merged.

Usage: ./create_native_cpu.sh <github_user> <ock_branch_to_create>

Note this deletes <ock-new-folder>

Description of change

Calls filter repo with paths from native_cpu_paths.txt with some renaming of folders.
It then merges to a llvm/intel repo and then does a small amount of post-processing which includes:

• Adding cmakes / altering cmakes and adding docs
• Removing some vecz lit tests which relate to old llvms
• swapping {{{undef|poison}} with poison in a lit test
• enabling -DNATIVECPU_USE_OCK=ON in .github/workflows/sycl-linux-build.yml
• Applying llvm clang-20 to files.