multi: replace ioutil.Discard

lnwire/onion_error.go

@@ -7,7 +7,6 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
-	"io/ioutil"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/go-errors/errors"
@@ -1304,7 +1303,7 @@ func DecodeFailure(r io.Reader, pver uint32) (FailureMessage, error) {
 		return nil, fmt.Errorf("unable to read pad len: %w", err)
 	}
 
-	if _, err := io.CopyN(ioutil.Discard, r, int64(padLength)); err != nil {
+	if _, err := io.CopyN(io.Discard, r, int64(padLength)); err != nil {
 		return nil, fmt.Errorf("unable to read padding %w", err)
 	}