Remove s390 files and cio_ignore stuff on s390x

[David Cantrell <dcantrell redhat com>]

First patch removes the bootdisk/s390 subdirectory since we
only build for s390x in RHEL-land now.  No need for this
directory.

The second patch removes the cio_ignore functionality
brought over from rhel5-branch.  This has been reverted
on rhel5, so I want to keep rawhide in sync.

-- 
David Cantrell <dcantrell redhat com>
Red Hat / Honolulu, HI