docs: Fix validation of spapr-vio addresses
docs: Fix validation of spapr-vio addresses

According to sPAPR, addresses are 32-bit (8 hex digits) rather
than 64-bit (16 hex digits). Update the schema accordingly.

Signed-off-by: Andrea Bolognani <3ada0bee826c753786fdbba72243dfba997094cf@redhat.com>
Reviewed-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

eskultety/libvirt,jardasgit/libvirt,nertpinx/libvirt,eskultety/libvirt,zippy2/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,olafhering/libvirt,nertpinx/libvirt,jfehlig/libvirt,eskultety/libvirt,libvirt/libvirt,jardasgit/libvirt,crobinso/libvirt,libvirt/libvirt,andreabolognani/libvirt,eskultety/libvirt,zippy2/libvirt,libvirt/libvirt,libvirt/libvirt,olafhering/libvirt,crobinso/libvirt,jardasgit/libvirt,zippy2/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,eskultety/libvirt,zippy2/libvirt,nertpinx/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,jfehlig/libvirt,andreabolognani/libvirt,nertpinx/libvirt,crobinso/libvirt,crobinso/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,jfehlig/libvirt,olafhering/libvirt,olafhering/libvirt,jardasgit/libvirt