vmm/virtualbox: Raise correct exception if VBox too old for parcel
vmm/virtualbox: Raise correct exception if VBox too old for parcel

- Fix stray use of an old variable when formatting the exception raised
when the installed VirtualBox is too old for the parcel's settings version

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr