multi: move several wait group done calls to defer statements

chainntnfs/btcdnotify/btcd.go

@@ -288,6 +288,8 @@ func (b *BtcdNotifier) onRedeemingTx(tx *btcutil.Tx, details *btcjson.BlockDetai
 // notificationDispatcher is the primary goroutine which handles client
 // notification registrations, as well as notification dispatches.
 func (b *BtcdNotifier) notificationDispatcher() {
+	defer b.wg.Done()
+
 out:
 	for {
 		select {
@@ -487,7 +489,6 @@ out:
 			break out
 		}
 	}
-	b.wg.Done()
 }
 
 // historicalConfDetails looks up whether a confirmation request (txid/output