chainregistry.go: export default values

This is needed so that git sees a subsequent commit as a code move.

fundingmanager_test.go

@@ -271,7 +271,7 @@ func createTestWallet(cdb *channeldb.DB, netParams *chaincfg.Params,
 		ChainIO:            bio,
 		FeeEstimator:       estimator,
 		NetParams:          *netParams,
-		DefaultConstraints: defaultBtcChannelConstraints,
+		DefaultConstraints: DefaultBtcChannelConstraints,
 	})
 	if err != nil {
 		return nil, err