suppress errors arising from deleting non-existent files during client uninstall
When rolling back partially configured IPA client a number of OSErrors pop up
due to uninstaller trying to remove files that do not exist anymore. This
patch supresses these errors while keeping them in log as debug messages.
https://fedorahosted.org/freeipa/ticket/4966
Reviewed-By: Martin Basti <mbasti@redhat.com>
Reviewed-By: Jan Cholasta <jcholast@redhat.com>