Description of problem:

If the `~/.ssh/config` file contains `Host example.com` directives, then `example.com` is autocompleted in `ssh <host>` but not if the `Host` directive is included from another file

Version-Release number of selected component (if applicable):

bash-completion-2.4-1.fc25.noarch

How reproducible:

Consistently

Steps to Reproduce:
1. Write this to `~/.ssh/config`:

```
Include config-not-read

Host works.example.com
        Host works.example.org
```

2. Write that to `~/.ssh/config-not-read`:

```
Host doesnot.example.com
        HostName doesnot.example.org
```

3. Type this `ssh works<tab><tab>`

4. Type that `ssh doesnot<tab><tab>`

Actual results:

[jkerry@localhost ~]$ ssh works.example.
works.example.com  works.example.org  
[jkerry@localhost ~]$ ssh doesnot
<empty line>

Expected results:

[jkerry@localhost ~]$ ssh works.example.
works.example.com  works.example.org  
[jkerry@localhost ~]$ ssh doesnot
doesnot.example.com  doesnot.example.org

Additional info:

I verified that it is not an SSH configuration issue by running `ssh -vvv doesnot.example.com` and checked that it does try to connect to `doesnot.example.org` instead.