Use --link-static with llvm-config where applicable
Use --link-static with llvm-config where applicable

LLVM 3.9 apparently added support for a monolithic dylib, which is defaults
to when you ask for the libraries to link against. Since we want static libs,
specifically ask llvm-config for them.

tari/llvm-sys.rs,tari/llvm-sys.rs,tari/llvm-sys.rs