fix error check in swarm connect

🤦‍♂️

fixes https://github.com/ipfs/go-ipfs/pull/6171/files/d21bb1eed85401412ad0e8749f60de75ee27051a#discussion_r271949856

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

core/coreapi/swarm.go

@@ -40,7 +40,7 @@ func (api *SwarmAPI) Connect(ctx context.Context, pi pstore.PeerInfo) error {
 		swrm.Backoff().Clear(pi.ID)
 	}
 
-	if err := api.peerHost.Connect(ctx, pi); err == nil {
+	if err := api.peerHost.Connect(ctx, pi); err != nil {
 		return err
 	}