Fix clippy error

This fixes the following error:

  error: this expression creates a reference which is immediately dereferenced by the compiler
     --> src/main.rs:165:27
      |
  165 |     let units = list_file(&file, endian)?;
      |                           ^^^^^ help: change this to: `file`
      |
      = note: `-D clippy::needless-borrow` implied by `-D warnings`
      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow



Signed-off-by: Andre Moreira Magalhaes <andrunko@gmail.com>

src/main.rs

@@ -165,7 +165,7 @@ fn process_file<E: Endianity>(
     endian: E,
     strip_prefix: Option<&String>,
 ) -> Result<Vec<Unit>> {
-    let units = list_file(&file, endian)?;
+    let units = list_file(file, endian)?;
     let units = if let Some(strip) = strip_prefix {
         units
             .iter()