cobbler ext_pillar params should be a dict

Otherwise:

Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/salt/pillar/__init__.py", line 423, in ext_pillar
    ext = self.ext_pillars[key](self.opts['id'], pillar, *val)
  File "/usr/lib/python2.6/site-packages/salt/pillar/cobbler.py", line 71, in ext_pillar
    result = {key: result}
TypeError: unhashable type: 'dict'