Windows: disable afsdhook.dll reload by daemon

Windows: disable afsdhook.dll reload by daemon

The daemon thread's loading and unloading of afsdhook.dll every
second prevents the disk drive from sleeping and forces a search
of the PATH.   Make the periodic reloading configurable and
disable it by default.

Change-Id: I7e1a5b2bc7e1c4d4ea39fc30cf34c1195a326ed2
Reviewed-on: http://gerrit.openafs.org/6715
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>