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_hir_analysis/src/variance/mod.rs

@@ -9,8 +9,9 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_middle::query::Providers;
 use rustc_middle::span_bug;
-use rustc_middle::ty::{self, CrateVariancesMap, GenericArgsRef, Ty, TyCtxt};
-use rustc_middle::ty::{TypeSuperVisitable, TypeVisitable};
+use rustc_middle::ty::{
+    self, CrateVariancesMap, GenericArgsRef, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable,
+};
 
 /// Defines the `TermsContext` basically houses an arena where we can
 /// allocate terms.