veyron/tools/mgmt/device: Add missing \n

Change-Id: Iab3ae3c4059094b432833873f7e7e0ed223c45d0
diff --git a/tools/mgmt/device/acl_impl.go b/tools/mgmt/device/acl_impl.go
index 02a81cc..e39f68e 100644
--- a/tools/mgmt/device/acl_impl.go
+++ b/tools/mgmt/device/acl_impl.go
@@ -43,7 +43,7 @@
 			entries.Tags(b)[tag] = true
 		}
 	}
-	fmt.Fprintf(cmd.Stdout(), "%v", entries)
+	fmt.Fprintln(cmd.Stdout(), entries)
 	return nil
 }
 
@@ -116,7 +116,7 @@
 		case err == nil:
 			return nil
 		}
-		fmt.Fprintf(cmd.Stderr(), "WARNING: trying again because of asynchronous change\n")
+		fmt.Fprintln(cmd.Stderr(), "WARNING: trying again because of asynchronous change")
 	}
 	return nil
 }