`stackoverflow` with nested `m/map-of`

this works

```clojure
(m/search dx100k
  {_ {_ {:db/id ?e
           :name  "Ivan"}}} ?e)
```
this not

```clojure
(m/rewrite dx100k
  (m/map-of _ (m/map-of _ {:db/id !e :name "Ivan"}))
  [!e ...])
```
code to reproduce

http://ix.io/2URI

stacktrace

http://ix.io/2URJ
