Link rustllvm statically, and distribute a static snapshot

In order to keep up to date with changes to the libraries that `llvm-config`
spits out, the dependencies to the LLVM are a dynamically generated rust file.
This file is now automatically updated whenever LLVM is updated to get kept
up-to-date.

At the same time, this cleans out some old cruft which isn't necessary in the
makefiles in terms of dependencies.

Closes #10745
Closes #10744

src/libsyntax/lib.rs

@@ -20,6 +20,7 @@
 
 #[license = "MIT/ASL2"];
 #[crate_type = "dylib"];
+#[crate_type = "rlib"];
 
 #[feature(macro_rules, globs, managed_boxes)];