Two new domain configuration XML elements are added to enable/disable
the protected key management operations for a guest:

    <domain>
      ...
      <keywrap>
        <cipher name='aes|dea' state='on|off'/>
      </keywrap>
      ...
    </domain>
Signed-off-by: NTony Krowiak <akrowiak@linux.vnet.ibm.com>
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Signed-off-by: NDaniel Hansel <daniel.hansel@linux.vnet.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>