Use proper TLV type for CommitmentSigned::funding_txid

Now that we are sure we will be moving forward with the `funding_txid`
TLV, we use the TLV type as mandated per the spec.

Author: wpaulino

lightning/src/ln/msgs.rs

@@ -2983,8 +2983,7 @@ impl_writeable_msg!(CommitmentSigned, {
 	signature,
 	htlc_signatures
 }, {
-	// TOOD(splicing): Change this to 1 once the spec is finalized
-	(1001, funding_txid, option),
+	(1, funding_txid, option),
 });
 
 #[cfg(taproot)]
@@ -2993,9 +2992,8 @@ impl_writeable_msg!(CommitmentSigned, {
 	signature,
 	htlc_signatures
 }, {
+	(1, funding_txid, option),
 	(2, partial_signature_with_nonce, option),
-	// TOOD(splicing): Change this to 1 and reorder once the spec is finalized
-	(1001, funding_txid, option),
 });
 
 impl_writeable!(DecodedOnionErrorPacket, {