Improved package excludes for CentOS 6/Docker

* Use wildcards to exclude firmware
* Exclude kernel packages
* Do not exclude MAKEDEV, which we use (and remove) in %post
I think you've fallen victim to the way the diff is displayed.  This change removes ``-MAKEDEV``, i.e., it stops removing the ``MAKEDEV``.  ``MAKEDEV`` is used in ``%post``, so we want it installed.  (Coincidentally, it was getting installed even though we had previously been requesting that it not be installed, so we got lucky.)