rust: kernel: get error::* items from the module

This is part of the effort to minimize the differences of the `rust`
branch with respect to mainline in order to eventually drop it.

Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: ojeda

rust/kernel/prelude.rs

@@ -37,6 +37,6 @@ pub use super::module_amba_driver;
 
 pub use super::static_assert;
 
-pub use super::{error::code::*, Error, Result};
+pub use super::error::{code::*, Error, Result};
 
 pub use super::{str::CStr, ARef, ThisModule};

rust/kernel/str.rs

@@ -6,7 +6,10 @@ use alloc::vec::Vec;
 use core::fmt::{self, Write};
 use core::ops::{self, Deref, Index};
 
-use crate::{bindings, error::code::*, Error};
+use crate::{
+    bindings,
+    error::{code::*, Error},
+};
 
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