CONFIG_DEV_ZERO is no longer needed in some defconfig files due to
- https://github.com/apache/nuttx/pull/15223
This PR removes CONFIG_DEV_ZERO from the affected defconfig files:
```bash
make distclean ; tools/refresh.sh --silent canmv230:knsh
make distclean ; tools/refresh.sh --silent canmv230:master
make distclean ; tools/refresh.sh --silent canmv230:nsbi
...
```
The failed builds above were extracted from [nuttx-prometheus-to-mastodon.json](https://lupyuen.org/articles/mastodon.html#appendix-post-nuttx-builds-to-mastodon)