runtime: skip TestG0StackOverflow on ios

This test fails when run on ios. (Although ios does not normally
support "exec", in the corellium environment it does.)

For #26061.

Change-Id: Idfdc53758aaabf0cb87ae50f9a4666deebf57fd6
Reviewed-on: https://go-review.googlesource.com/c/go/+/487355
TryBot-Result: Gopher Robot <[email protected]>
Auto-Submit: Bryan Mills <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>
Run-TryBot: Bryan Mills <[email protected]>

Author: Bryan C. Mills

src/runtime/crash_test.go

@@ -782,7 +782,7 @@ func TestG0StackOverflow(t *testing.T) {
 	testenv.MustHaveExec(t)
 
 	switch runtime.GOOS {
-	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "android":
+	case "android", "darwin", "dragonfly", "freebsd", "ios", "linux", "netbsd", "openbsd":
 		t.Skipf("g0 stack is wrong on pthread platforms (see golang.org/issue/26061)")
 	}