Reformat use declarations.

The previous commit updated `rustfmt.toml` appropriately. This commit is
the outcome of running `x fmt --all` with the new formatting options.

compiler/rustc_const_eval/src/const_eval/mod.rs

@@ -1,10 +1,9 @@
 // Not in interpret to make sure we do not use private implementation details
 
-use rustc_middle::bug;
-use rustc_middle::mir;
 use rustc_middle::mir::interpret::InterpErrorInfo;
 use rustc_middle::query::{Key, TyCtxtAt};
 use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::{bug, mir};
 use rustc_target::abi::VariantIdx;
 use tracing::instrument;