exporter: remove non dist options from tar exporter

This option looks like a mistake added in 45fc3ed.
These options aren't ever used, so we don't need to parse them, we can
just silently discard them.

Signed-off-by: Justin Chadwell <[email protected]>

Author: jedevc

exporter/tar/export.go

@@ -3,7 +3,6 @@ package local
 import (
 	"context"
 	"os"
-	"strconv"
 	"strings"
 	"time"
 
@@ -20,13 +19,6 @@ import (
 	fstypes "github.com/tonistiigi/fsutil/types"
 )
 
-const (
-	// preferNondistLayersKey is an exporter option which can be used to mark a layer as non-distributable if the layer reference was
-	// already found to use a non-distributable media type.
-	// When this option is not set, the exporter will change the media type of the layer to a distributable one.
-	preferNondistLayersKey = "prefer-nondist-layers"
-)
-
 type Opt struct {
 	SessionManager *session.Manager
 }
@@ -47,25 +39,14 @@ func (e *localExporter) Resolve(ctx context.Context, opt map[string]string) (exp
 	if err != nil {
 		return nil, err
 	}
-
-	for k, v := range opt {
-		switch k {
-		case preferNondistLayersKey:
-			b, err := strconv.ParseBool(v)
-			if err != nil {
-				return nil, errors.Wrapf(err, "non-bool value for %s: %s", preferNondistLayersKey, v)
-			}
-			li.preferNonDist = b
-		}
-	}
+	_ = opt
 
 	return li, nil
 }
 
 type localExporterInstance struct {
 	*localExporter
-	opts          local.CreateFSOpts
-	preferNonDist bool
+	opts local.CreateFSOpts
 }
 
 func (e *localExporterInstance) Name() string {