DAFS: Skip hosts with invalid flags on restore

DAFS: Skip hosts with invalid flags on restore

Host entries with HWHO_INPROGRESS set or ALTADDR unset do not have
valid state, since those flags indicate that the fileserver was in the
middle of identifying the host when the host struct was serialized.
Skip entries from the on-disk host data that have such invalid flags
set when restoring state, so we do not load invalid data.

Reviewed-on: http://gerrit.openafs.org/5527
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit 6e7b31ef0a69b8ea39e8acc474a7aab48f828d3d)

Change-Id: Ifa69ec30bda8f9ba162954d39f9b60d9fc630289
Reviewed-on: http://gerrit.openafs.org/5545
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>