multi: rename NewFundingLocked to NewChannelReady

This commit is created by the following command,

```shell
gofmt -d -w -r 'NewFundingLocked -> NewChannelReady' .
```

lnwire/funding_locked.go

@@ -35,7 +35,7 @@ type ChannelReady struct {
 
 // NewFundingLocked creates a new FundingLocked message, populating it with the
 // necessary IDs and revocation secret.
-func NewFundingLocked(cid ChannelID, npcp *btcec.PublicKey) *ChannelReady {
+func NewChannelReady(cid ChannelID, npcp *btcec.PublicKey) *ChannelReady {
 	return &ChannelReady{
 		ChanID:                 cid,
 		NextPerCommitmentPoint: npcp,

lnwire/lnwire_test.go

@@ -580,7 +580,7 @@ func TestLightningWireProtocol(t *testing.T) {
 				return
 			}
 
-			req := NewFundingLocked(ChannelID(c), pubKey)
+			req := NewChannelReady(ChannelID(c), pubKey)
 
 			v[0] = reflect.ValueOf(*req)
 		},

lnwire/message_test.go

@@ -452,7 +452,7 @@ func newMsgFundingLocked(t testing.TB, r io.Reader) *lnwire.ChannelReady {
 
 	pubKey := randPubKey(t)
 
-	msg := lnwire.NewFundingLocked(lnwire.ChannelID(c), pubKey)
+	msg := lnwire.NewChannelReady(lnwire.ChannelID(c), pubKey)
 	msg.ExtraData = createExtraData(t, r)
 
 	return msg