Moved support code for rustc_mir::borrow_check query out of mod transform.

Author: pnkfelix

src/librustc_mir/borrow_check.rs

@@ -31,7 +31,6 @@ pub mod simplify;
 pub mod erase_regions;
 pub mod no_landing_pads;
 pub mod type_check;
-pub mod borrow_check;
 pub mod rustc_peek;
 pub mod elaborate_drops;
 pub mod add_call_guards;