[PATCH] rust: avoid unused import warning in `rusttest`

[Miguel Ojeda]

When compiling for the `rusttest` target, the `core::ptr` import is
unused since its only use happens in the `reserve()` method which is
not compiled in that target:

    warning: unused import: `core::ptr`
    --> rust/kernel/alloc/vec_ext.rs:7:5
      |
    7 | use core::ptr;
      |     ^^^^^^^^^
      |
      = note: `#[warn(unused_imports)]` on by default

Thus clean it.

Fixes: 97ab3e8eec0c ("rust: alloc: fix dangling pointer in VecExt<T>::reserve()")
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
---
 rust/kernel/alloc/vec_ext.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/rust/kernel/alloc/vec_ext.rs b/rust/kernel/alloc/vec_ext.rs
index e9a81052728a..1297a4be32e8 100644
--- a/rust/kernel/alloc/vec_ext.rs
+++ b/rust/kernel/alloc/vec_ext.rs
@@ -4,7 +4,6 @@
 
 use super::{AllocError, Flags};
 use alloc::vec::Vec;
-use core::ptr;
 
 /// Extensions to [`Vec`].
 pub trait VecExt<T>: Sized {
@@ -141,7 +140,11 @@ fn reserve(&mut self, additional: usize, flags: Flags) -> Result<(), AllocError>
         // `krealloc_aligned`. A `Vec<T>`'s `ptr` value is not guaranteed to be NULL and might be
         // dangling after being created with `Vec::new`. Instead, we can rely on `Vec<T>`'s capacity
         // to be zero if no memory has been allocated yet.
-        let ptr = if cap == 0 { ptr::null_mut() } else { old_ptr };
+        let ptr = if cap == 0 {
+            core::ptr::null_mut()
+        } else {
+            old_ptr
+        };
 
         // SAFETY: `ptr` is valid because it's either NULL or comes from a previous call to
         // `krealloc_aligned`. We also verified that the type is not a ZST.

base-commit: 97ab3e8eec0ce79d9e265e6c9e4c480492180409
-- 
2.45.1