Cleanup SELinux policy
* Remove FC for /usr/libexec/ipa/com.redhat.idm.trust-fetch-domains. The
file has been moved to oddjobs/ subdirectory a long time ago.
* Simplify FC for oddjob scripts. All com.redhat.idm.* and org.freeipa.*
scripts are labeled as ipa_helper_exec_t.
* use miscfiles_read_generic_certs() instead of deprecated
miscfiles_read_certs() to address the warning:
```
Warning: miscfiles_read_certs() has been deprecated, please use miscfiles_read_generic_certs() instead.
```
(Also add org.freeipa.server.trust-enable-agent to .gitignore)
Related: https://pagure.io/freeipa/issue/6891
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Florence Blanc-Renaud <flo@redhat.com>