cmd/upspinfs: fix error messages in TestSymlink

The two final error messages in TestSymlink look reversed to me.

Change-Id: I16da4fc2e9eb303f57abc5e5458709561e405b1f
Reviewed-on: https://upspin-review.googlesource.com/c/upspin/+/19300
Reviewed-by: Andrew Gerrand <adg@golang.org>
Reviewed-by: David Presotto <presotto@gmail.com>
diff --git a/cmd/upspinfs/upspinfs_test.go b/cmd/upspinfs/upspinfs_test.go
index d39c596..882af84 100644
--- a/cmd/upspinfs/upspinfs_test.go
+++ b/cmd/upspinfs/upspinfs_test.go
@@ -444,11 +444,11 @@
 
 	// Test a path that leaves Upspin. It should fail.
 	if err := os.Symlink("../../../../quux", filepath.Join(subdir, "wontwork")); err == nil {
-		fatal(t, err)
+		t.Fatalf("symlink out of upspin worked but should not have")
 	}
 
 	if err := os.RemoveAll(testDir); err != nil {
-		t.Fatalf("symlink out of upspin worked but should not have")
+		fatal(t, err)
 	}
 }