[CI] Use powershell to download LLVM on windows, split macOS and linux.
[CI] Use powershell to download LLVM on windows, split macOS and linux.

gingerBill/Odin,gingerBill/Odin,gingerBill/Odin,ThisDrunkDane/Odin,ThisDrunkDane/Odin,ThisDrunkDane/Odin,gingerBill/Odin