https: T9559: fix bogus port conflict with "vrf default"

Committing "set service https vrf default" failed with "TCP port 443 in vrf
default is already used by another service" although nothing listened on the
port. The port check bound its test socket to a VRF device named "default",
which does not exist, and reported that failure as a port conflict.

The default VRF is now treated like no VRF at all. A VRF device that does not
exist no longer counts as a busy port, as nothing can listen in it; any other
error is raised instead of being reported as a conflict. The same check is
used by the Prometheus VPP exporter.

0 files changed, 0 insertions, 0 deletions