multi: add NewLogClosure in lnutils to avoid repetition

And replaces all usage of `logClosure` with `lnutils.LogClosure`.

contractcourt/chain_watcher.go

@@ -20,6 +20,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/lnutils"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
 )
@@ -1254,7 +1255,7 @@ func (c *chainWatcher) dispatchContractBreach(spendEvent *chainntnfs.SpendDetail
 	spendHeight := uint32(spendEvent.SpendingHeight)
 
 	log.Debugf("Punishment breach retribution created: %v",
-		newLogClosure(func() string {
+		lnutils.NewLogClosure(func() string {
 			retribution.KeyRing.LocalHtlcKey = nil
 			retribution.KeyRing.RemoteHtlcKey = nil
 			retribution.KeyRing.ToLocalKey = nil