[clang] [clang][deps] Skip slow `UNHASHED_CONTROL_BLOCK` records (PR #69975)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 commented:

Besides deps scanning, have you tried to enable these option to compile with clang modules? I mean, if it is safe to enable such options at compilation times, it looks a valid optimization for C++20 modules too. If it is not safe to do so, I think we need  to document it explicitly.

https://github.com/llvm/llvm-project/pull/69975