remove re-export of parking_lot in util (#6435)

sync/src/light_sync/mod.rs

@@ -45,7 +45,8 @@ use light::net::{
 };
 use light::request::{self, CompleteHeadersRequest as HeadersRequest};
 use network::PeerId;
-use util::{U256, H256, Mutex, RwLock};
+use util::{U256, H256};
+use parking_lot::{Mutex, RwLock};
 use rand::{Rng, OsRng};
 
 use self::sync_round::{AbortReason, SyncRound, ResponseContext};

sync/src/light_sync/tests/test_net.rs

@@ -29,7 +29,7 @@ use light::client::Client as LightClient;
 use light::net::{LightProtocol, IoContext, Capabilities, Params as LightParams};
 use light::provider::LightProvider;
 use network::{NodeId, PeerId};
-use util::RwLock;
+use parking_lot::RwLock;
 
 use time::Duration;
 use light::cache::Cache;