Add test case explicitly defining a smartcard host certificates
database via the following xml:

    <smartcard mode='host-certificates'>
      <database>/tmp/foo</database>
    </smartcard>

This case is not currently covered in the test suite.
Signed-off-by: NAnya Harter <aharter@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>