ubik: Do not count votes from error'd connections

If the given connection has a connection-wide error on it, the vote we
got from that site is probably not valid, and we could easily be
interpreting an error code as a vote time. So instead, treat the host
as if we got a network error from it.

Reviewed-on: http://gerrit.openafs.org/8487
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit 23092acce5d2d71a5ad6402119973c7c2c2f5e89)

Change-Id: Id320b33bb6662d7867ae1f4a8d0a29808f16b59d
Reviewed-on: http://gerrit.openafs.org/8947
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Simon Wilkinson <simonxwilkinson@gmail.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>