Fix formatting in xarray module to comply with kernel coding
guidelines:

- Update use clauses to use vertical layout with each import on its
  own line.
- Add trailing empty comments to preserve formatting and prevent
  rustfmt from collapsing imports.
- Break long assert_eq! statement in documentation across multiple
  lines for better readability.

Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Assisted-by: LLM
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/xarray.rs | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/rust/kernel/xarray.rs b/rust/kernel/xarray.rs
index 987c9c0c21989..02f93ae1f92de 100644
--- a/rust/kernel/xarray.rs
+++ b/rust/kernel/xarray.rs
@@ -4,20 +4,33 @@
 //!
 //! C header: [`include/linux/xarray.h`](srctree/include/linux/xarray.h)
 
-use crate::{
+use core::{
+    iter,
+    marker::PhantomData,
+    pin::Pin,
+    ptr::NonNull, //
+};
+use kernel::{
     alloc,
     bindings,
-    build_assert::build_assert,
-    error::{Error, Result},
+    build_assert::build_assert, //
+    error::{
+        Error,
+        Result, //
+    },
     ffi::c_void,
     types::{
         ForeignOwnable,
         NotThreadSafe,
         Opaque, //
-    }, //
+    },
+};
+use pin_init::{
+    pin_data,
+    pin_init,
+    pinned_drop,
+    PinInit, //
 };
-use core::{iter, marker::PhantomData, pin::Pin, ptr::NonNull};
-use pin_init::{pin_data, pin_init, pinned_drop, PinInit};
 
 /// An array which efficiently maps sparse integer indices to owned objects.
 ///
@@ -50,7 +63,10 @@
 /// *guard.get_mut(0).unwrap() = 0xffff;
 /// assert_eq!(guard.get(0).copied(), Some(0xffff));
 ///
-/// assert_eq!(guard.store(0, beef, GFP_KERNEL)?.as_deref().copied(), Some(0xffff));
+/// assert_eq!(
+///     guard.store(0, beef, GFP_KERNEL)?.as_deref().copied(),
+///     Some(0xffff)
+/// );
 /// assert_eq!(guard.get(0).copied(), Some(0xbeef));
 ///
 /// guard.remove(0);

-- 
2.51.2