Add the chain subsystem logger to btcrpcclient.

Logging from btcrpcclient is currently not possible to set, and defaults
to nothing. Letting it inherit chain's logger can greatly simplify
debugging of connectivity issues.

Also remove a now redundant log message upon connecting to btcd.

chain/chain.go

@@ -224,7 +224,6 @@ func parseBlock(block *btcjson.BlockDetails) (*wtxmgr.BlockMeta, error) {
 }
 
 func (c *Client) onClientConnect() {
-	log.Info("Established websocket RPC connection to btcd")
 	select {
 	case c.enqueueNotification <- ClientConnected{}:
 	case <-c.quit:

log.go

@@ -21,6 +21,7 @@ import (
 	"os"
 
 	"github.com/btcsuite/btclog"
+	"github.com/btcsuite/btcrpcclient"
 	"github.com/btcsuite/btcwallet/chain"
 	"github.com/btcsuite/btcwallet/wallet"
 	"github.com/btcsuite/btcwallet/wtxmgr"
@@ -92,6 +93,7 @@ func useLogger(subsystemID string, logger btclog.Logger) {
 	case "CHNS":
 		chainLog = logger
 		chain.UseLogger(logger)
+		btcrpcclient.UseLogger(logger)
 	}
 }