Check for freeipa-server-dns package early
The ``--setup-dns`` knob and interactive installer now check for
presence of freeipa-server-dns early and stop the installer with an
error.
```
$ ipa-server-install
...
Do you want to configure integrated DNS (BIND)? [no]: yes
Integrated DNS requires 'freeipa-server-dns' package
The ipa-server-install command failed. See /var/log/ipaserver-install.log for more information
```
```
$ ipa-server-install --setup-dns
Usage: ipa-server-install [options]
ipa-server-install: error: option setup-dns: Integrated DNS requires 'freeipa-server-dns' package
The ipa-server-install command failed.
```
Fixes: https://pagure.io/freeipa/issue/7577
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>