Also disallow active devices with internal kernel names.

The same problem fixed in commit 438cf1d1 is present in libdevmapper wrapper when parsing active device table.

The whole point of conversion was that non-authenticated modes can be always represented in the old cipher-mode-iv format. As the internal names contains dash, these are unsupported.

That said, the libdevmapper backend now correctly returns full cipher specification including capi prefix for this case.

Init_by_name call now fails with incomplatible cipher definition error.