docs: fix typo in rust/kernel/str.rs

index fb61ce81e..42f355f74 100644
@@ -752,7 +752,7 @@ pub(crate) unsafe fn from_ptrs(pos: *mut u8, end: *mut u8) -> Self {
     /// for the lifetime of the returned [`RawFormatter`].
     pub(crate) unsafe fn from_buffer(buf: *mut u8, len: usize) -> Self {
         let pos = buf as usize;
-        // INVARIANT: We ensure that `end` is never less then `buf`, and the safety requirements
+        // INVARIANT: We ensure that `end` is never less than `buf`, and the safety requirements
         // guarantees that the memory region is valid for writes.
         Self {
             pos,