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_transmute/src/layout/dfa.rs

@@ -1,9 +1,11 @@
-use super::{nfa, Byte, Nfa, Ref};
-use crate::Map;
 use std::fmt;
 use std::sync::atomic::{AtomicU32, Ordering};
+
 use tracing::instrument;
 
+use super::{nfa, Byte, Nfa, Ref};
+use crate::Map;
+
 #[derive(PartialEq, Clone, Debug)]
 pub(crate) struct Dfa<R>
 where

compiler/rustc_transmute/src/layout/mod.rs

@@ -60,9 +60,10 @@ impl Ref for ! {
 
 #[cfg(feature = "rustc")]
 pub mod rustc {
+    use std::fmt::{self, Write};
+
     use rustc_middle::mir::Mutability;
     use rustc_middle::ty::{self, Ty};
-    use std::fmt::{self, Write};
 
     /// A reference in the layout.
     #[derive(Debug, Hash, Eq, PartialEq, Clone, Copy)]

compiler/rustc_transmute/src/layout/nfa.rs

@@ -1,8 +1,9 @@
-use super::{Byte, Ref, Tree, Uninhabited};
-use crate::{Map, Set};
 use std::fmt;
 use std::sync::atomic::{AtomicU32, Ordering};
 
+use super::{Byte, Ref, Tree, Uninhabited};
+use crate::{Map, Set};
+
 /// A non-deterministic finite automaton (NFA) that represents the layout of a type.
 /// The transmutability of two given types is computed by comparing their `Nfa`s.
 #[derive(PartialEq, Debug)]

compiler/rustc_transmute/src/layout/tree.rs

@@ -1,6 +1,7 @@
-use super::{Byte, Def, Ref};
 use std::ops::ControlFlow;
 
+use super::{Byte, Def, Ref};
+
 #[cfg(test)]
 mod tests;
 
@@ -170,24 +171,14 @@ where
 
 #[cfg(feature = "rustc")]
 pub(crate) mod rustc {
+    use rustc_middle::ty::layout::{HasTyCtxt, LayoutCx, LayoutError, LayoutOf};
+    use rustc_middle::ty::{self, AdtDef, AdtKind, List, ScalarInt, Ty, TyCtxt, TypeVisitableExt};
+    use rustc_span::ErrorGuaranteed;
+    use rustc_target::abi::{FieldsShape, Size, TyAndLayout, Variants};
+
     use super::Tree;
     use crate::layout::rustc::{Def, Ref};
 
-    use rustc_middle::ty::layout::HasTyCtxt;
-    use rustc_middle::ty::layout::LayoutCx;
-    use rustc_middle::ty::layout::LayoutError;
-    use rustc_middle::ty::layout::LayoutOf;
-    use rustc_middle::ty::AdtDef;
-    use rustc_middle::ty::AdtKind;
-    use rustc_middle::ty::List;
-    use rustc_middle::ty::ScalarInt;
-    use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
-    use rustc_span::ErrorGuaranteed;
-    use rustc_target::abi::FieldsShape;
-    use rustc_target::abi::Size;
-    use rustc_target::abi::TyAndLayout;
-    use rustc_target::abi::Variants;
-
     #[derive(Debug, Copy, Clone)]
     pub(crate) enum Err {
         /// The layout of the type is not yet supported.