When support for dmi-to-pci-bridge was added, it was assumed that,
just as with the pci-root bus, slot 0 was reserved. This is not the
case - it can be used to connect a device just like any other slot, so
remove the restriction and update the test cases that auto-assign an
address on a dmi-to-pci-bridge.
Per-domain directories were introduced in order to be able to
completely separate security labels for each domain (commit
f1f68ca334). However when the domain
name is long (let's say a ridiculous 110 characters), we cannot
connect to the monitor socket because on length of UNIX socket address
is limited. In order to get around this, let's shorten it in similar
fashion and in order to avoid conflicts, throw in an ID there as well.
Also save that into the status XML and load the old status XMLs
properly (to clean up after older domains). That way we can change it
in the future.
The shortening can be seen in qemuxml2argv tests, for example in the
hugepages-pages2 case.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>