Revert "PR#3568: kiwi: don't bind builders's /dev"
    
    This reverts commit 56cea9adc25216bbb162d65a359013ef81267652, reversing
    changes made to e9b5ec215d1f1e40ef177b9146a90508f0b9126f.
    
    mock was changed meanwhile to automatically bind device mapper into the
    buildroot.
    
    Related: https://pagure.io/koji/issue/3567
    https://pagure.io/koji/pull-request/3585
    https://github.com/rpm-software-management/mock/pull/1005