A couple NHG messages we were logging as errors are a bit spammy
in usecases where you routinely add/remove interfaces (VM heavy
deployments). Its not really an error a user cares about and
more for a developer to know what went wrong after the fact so
it makes more sense for these to be under a debug rather than
an error since seeing them does not implicitly mean error during
those usecases.
Signed-off-by: Stephen Worley <sworley@nvidia.com>