viced: remove dead code CheckHost()

Remove CheckHost().

Change-Id: I618066d28ef64fdfe94d5ab08ef89adb08a99fd6
Reviewed-on: http://gerrit.openafs.org/10580
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>