remove unused comment

src/main.rs

@@ -193,7 +193,7 @@ fn calc_file_digest(digest: &mut dyn Digest, file_name: &str) -> XResult<String>
             Ok(0) => { pb.finish_and_clear(); return Ok(digest.result_str()); },
             Ok(len) => len,
             Err(ref e) if e.kind() == ErrorKind::Interrupted => continue,
-            Err(e) => return Ok(format!("ERROR: {}", e)),//Err(Box::new(e)),
+            Err(e) => return Ok(format!("ERROR: {}", e)),
         };
         digest.input(&buf[..len]);
         processed += len as u64;