fix(cli): use div_ceil for list ABI test

The Rust CLI clippy gate treats the hand-written alignment rounding in the
multi-file list projection layout test as a manual div-ceil implementation.
Use the standard integer operation so the test remains clear, equivalent, and
warning-free under the repository's deny-warnings policy.

Test Plan:
- `cargo fmt --manifest-path rust/cli/Cargo.toml --all` -- passed
- `ulimit -v 41943040; CARGO_BUILD_JOBS=1 cargo clippy --manifest-path rust/cli/Cargo.toml --all-targets -- -D warnings` -- passed

rust/src/fileio_prefs.rs

@@ -2631,9 +2631,8 @@ mod tests {
         let callback = size_of::<Option<FIO_listMultipleFilesDisplayFn>>();
         let projection_alignment = align_of::<FIO_listFileInfoProjection_t>();
         let projection_payload = 2 * size_of::<u64>() + 4 * size_of::<c_int>() + size_of::<u32>();
-        let projection_size = (projection_payload + projection_alignment - 1)
-            / projection_alignment
-            * projection_alignment;
+        let projection_size =
+            projection_payload.div_ceil(projection_alignment) * projection_alignment;
 
         assert_eq!(
             align_of::<FIO_listFileInfoProjection_t>(),