Fix lints (#1716)

Summary:
Fix a lint that's currently failing.
See https://github.com/facebook/flipper/runs/1449249447?check_suite_focus=true

Pull Request resolved: https://github.com/facebook/flipper/pull/1716

Test Plan: cargo clippy succeeds now.

Reviewed By: nikoant

Differential Revision: D25170963

Pulled By: passy

fbshipit-source-id: 658f8b6abaef9860be9ff07447d2354727acb7c7

packer/src/main.rs

@@ -69,7 +69,7 @@ fn pack(
     let packtype_paths = pack_list
         .0
         .get(&platform)
-        .ok_or_else(|| error::Error::MissingPlatformDefinition(platform))?;
+        .ok_or(error::Error::MissingPlatformDefinition(platform))?;
     let res = packtype_paths
         .into_par_iter()
         .map(|(&pack_type, pack_files)| {

packer/src/types.rs

@@ -19,15 +19,7 @@ arg_enum! {
 }
 
 #[derive(
-    Debug,
+    Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, serde::Deserialize, serde::Serialize,
-    Clone,
-    Copy,
-    PartialEq,
-    Eq,
-    PartialOrd,
-    Ord,
-    serde::Deserialize,
-    serde::Serialize
 )]
 #[serde(rename_all = "lowercase")]
 pub enum PackType {