pkg/list: fix typo

Change-Id: I9becdc016839e1a7d4ae7302be265ffe489e1753
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/4980
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
diff --git a/pkg/list/sort.go b/pkg/list/sort.go
index 7b3e526..6947aab 100644
--- a/pkg/list/sort.go
+++ b/pkg/list/sort.go
@@ -49,7 +49,7 @@
 //
 //    Sort([2, 3, 1], list.Ascending)
 //
-//    Sort{{a: 2}, {a: 3}, {a: 1}, {a: {}, b: {}, less: x.a < y.a}}
+//    Sort{{a: 2}, {a: 3}, {a: 1}, {x: {}, y: {}, less: x.a < y.a}}
 //
 func Sort(list []cue.Value, cmp cue.Value) (sorted []cue.Value, err error) {
 	s := valueSorter{list, cmp, nil}