lnwallet+funding+lnd: trim unused parameters, from lnwallet.Config

chainreg: remove unused GenDefaultBtcConstraints

lnwallet+funding+lnd: remove DefaultDustLimit from lnwallet.Config

lnwallet/parameters.go

@@ -80,3 +80,8 @@ func DustLimitForSize(scriptSize int) btcutil.Amount {
 
 	return dustlimit
 }
+
+// DustLimitUnknownWitness returns the dust limit for an UnknownWitnessSize.
+func DustLimitUnknownWitness() btcutil.Amount {
+	return DustLimitForSize(input.UnknownWitnessSize)
+}