rust: block: normalize imports for gen_disk.rs

Clean up the import statements in `gen_disk.rs` to make the code easier to
maintain.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/r/20250902-rnull-up-v6-16-v7-7-b5212cc89b98@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Andreas Hindborg

rust/kernel/block/mq/gen_disk.rs

@@ -5,9 +5,13 @@
 //! C header: [`include/linux/blkdev.h`](srctree/include/linux/blkdev.h)
 //! C header: [`include/linux/blk_mq.h`](srctree/include/linux/blk_mq.h)
 
-use crate::block::mq::{raw_writer::RawWriter, Operations, TagSet};
-use crate::{bindings, error::from_err_ptr, error::Result, sync::Arc};
-use crate::{error, static_lock_class};
+use crate::{
+    bindings,
+    block::mq::{raw_writer::RawWriter, Operations, TagSet},
+    error::{self, from_err_ptr, Result},
+    static_lock_class,
+    sync::Arc,
+};
 use core::fmt::{self, Write};
 
 /// A builder for [`GenDisk`].