[compiler-rt] [libc] [libc][sched] Implement proxy headers for `cpu_set_t`, `struct sched_param` and `sched_macros`. (PR #126303)

[Krishna Pandey via llvm-commits]

krishna2803 wrote:

commit [3f67c429](https://github.com/llvm/llvm-project/pull/126303/commits/3f67c42904757958fe9b30db1e37429ef1c0dfde) suggests we can safely remove the include for `sched.h` from `compiler-rt/lib/scudo/standalone/mem_map_linux.cpp`

https://github.com/llvm/llvm-project/pull/126303