Although I'm not a big fan of using `OS_NAME` in easyconfig files, I feel like this is a good thing to do since we don't have a better alternative yet...

However, I would approach it differently. Before this patch, `libibverbs-devel` was enforced. Since this is clearly wrong for Debian/Ubuntu, it should be adjusted, but the catch-all should remains `libibverbs-devel`, thus, I suggest:

```python
if OS_NAME in ['debian', 'ubuntu']:
    osdependencies = ['libibverbs-dev']
else:
    # OK for OS_NAME == redhat, Fedora, RHEL, SL, centos
    osdependencies = ['libibverbs-devel']
```

That way, the catch-all remains the same (until someone else steps in and corrects it for other OS families).

Also: this change should be applied consistently across all `OpenMPI` easyconfigs that use `--with-openib`.

@ajdecon: I'll issue a PR to your repo to handle this, coming up in a bit...