Update src/mir/optimizations.md

Co-Authored-By: Who? Me?! <[email protected]>

Author: spastorino

src/mir/optimizations.md

@@ -22,9 +22,9 @@ run and that some validation has occurred. Then, it [steals][steal] the MIR
 optimizes it, and returns the improved MIR.
 
 [optmir]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_mir/transform/fn.optimized_mir.html
-[query]: https://rustc-dev-guide.rust-lang.org/query.html
-[defid]: https://rustc-dev-guide.rust-lang.org/appendix/glossary.html?highlight=DefId#appendix-c-glossary
-[steal]: https://rustc-dev-guide.rust-lang.org/mir/passes.html?highlight=steal#stealing
+[query]: ../query.md
+[defid]: ../appendix/glossary.md
+[steal]: ../passes.md#stealing
 
 ## Defining optimization passes