Add Fields type alias to log package

Signed-off-by: Maksym Pavlenko <pavlenko.maksym@gmail.com>

cmd/containerd/command/main.go

@@ -174,7 +174,7 @@ can be used and modified as necessary as a custom configuration.`
 			log.G(ctx).WithError(w).Warn("cleanup temp mount")
 		}
 
-		log.G(ctx).WithFields(logrus.Fields{
+		log.G(ctx).WithFields(log.Fields{
 			"version":  version.Version,
 			"revision": version.Revision,
 		}).Info("starting containerd")

cmd/ctr/commands/content/prune.go

@@ -81,7 +81,7 @@ var pruneReferencesCommand = cli.Command{
 
 			for k := range info.Labels {
 				if isLayerLabel(k) {
-					log.G(ctx).WithFields(logrus.Fields{
+					log.G(ctx).WithFields(log.Fields{
 						"digest": info.Digest,
 						"label":  k,
 					}).Debug("Removing label")