add flags support to virStorageVolCreateXML
add flags support to virStorageVolCreateXML

Signed-off-by: Vasiliy Tolstov <c36af997645181f727020b1671b7c66b7a9c7a34@selfip.ru>

tucksaun/libvirt-php,tucksaun/libvirt-php,libvirt/libvirt-php,zippy2/libvirt-php,zippy2/libvirt-php,tucksaun/libvirt-php,libvirt/libvirt-php,tucksaun/libvirt-php,libvirt/libvirt-php,zippy2/libvirt-php