cmd/go: re-enable TestCgoConsistentResults on solaris

Updates #13247.

Change-Id: If5e4c9f4db05f58608b0eeed1a2312a04015b207
Reviewed-on: https://go-review.googlesource.com/23741
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/cmd/go/go_test.go

@@ -2778,10 +2778,6 @@ func TestCgoConsistentResults(t *testing.T) {
 	if !canCgo {
 		t.Skip("skipping because cgo not enabled")
 	}
-	if runtime.GOOS == "solaris" {
-		// See https://golang.org/issue/13247
-		t.Skip("skipping because Solaris builds are known to be inconsistent; see #13247")
-	}
 
 	tg := testgo(t)
 	defer tg.cleanup()