utils: T9322: simplify address assignment lookup and document ValueError

The lookup for an address on all interfaces carried a copy of the zone
index and VRF filtering that already exists in the lookup returning the
matching interfaces. It now delegates to it, so the two cannot drift.

The per-interface address match is written as a single condition, the
comments are trimmed, and the docstrings state that anything but a
single address raises ValueError instead of being reported as not
assigned.

The sflow zone index smoketest removes the dummy interface it creates,
and the unit tests drop a stale task reference and a duplicate import.

0 files changed, 0 insertions, 0 deletions