[clang] Added partial support for compiling C++20 modules and header-units without scanning. (PR #147682)

[Hassan Sajjad via cfe-commits]

HassanSajjad-302 wrote:

Simplified quite a lot and based it on the latest commit. Lots of new features have been added in HMake including the zero-cost Adaptive Jumbo Build. Please give this a read ( 2min) https://github.com/HassanSajjad-302/HMake/discussions/4

https://github.com/llvm/llvm-project/pull/147682