lnd: use cfg.Bitcoin.DefaultNumChanConfs

lnd.go

@@ -302,7 +302,7 @@ func lndMain() error {
 			// TODO(roasbeef): add configurable mapping
 			//  * simple switch initially
 			//  * assign coefficient, etc
-			return uint16(cfg.DefaultNumChanConfs)
+			return uint16(cfg.Bitcoin.DefaultNumChanConfs)
 		},
 		RequiredRemoteDelay: func(chanAmt btcutil.Amount) uint16 {
 			// TODO(roasbeef): add additional hooks for