virt-driver-vz: Require parallels-7.0.22 at least

virt-driver-vz: Require parallels-7.0.22 at least

With the latest patch to the vz driver (7d73ca06cefe) I was
getting some compilation errors. It turned out, my installation
of the parallels SDK was not as fresh as it could be. Parallels
installed in my system were missing the
PRL_USE_VNET_NAME_FOR_BRIDGE_NAME symbol which simply was not
introduced at the time I was installing the SDK. The symbol was
introduced in 86e62a5d which was then part of the 7.0.22 release.
Require that version at least therefore.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>