Revert "try using appveyor's llvm copy"
Revert "try using appveyor's llvm copy"

This reverts commit 35dc987dc88712d6e70f3b8c9cd076fe43fcd874.

andrewrk/zig,zig-lang/zig,andrewrk/zig,raulgrell/zig,Dimenus/zig,raulgrell/zig,Dimenus/zig,raulgrell/zig,raulgrell/zig,raulgrell/zig,zig-lang/zig,zig-lang/zig,Dimenus/zig