Title: #334: Print a warning when enumeration is requested but disabled
The patches now look good, but please squash the three commits into a single one so I can
push a single patch.
You can run `git rebase -i origin/master` in your branch and then change the `pick` word
to `fixup` in the second and third patch so that the patches will be merged into one.
Let me know if you need any help doing this.
See the full comment at https://github.com/SSSD/sssd/pull/334#issuecomment-330496087