Windows: ignore SYNCHRONIZE privilege in cm_CheckNTOpen

Windows: ignore SYNCHRONIZE privilege in cm_CheckNTOpen

SYNCHRONIZE has not meaning for AFS so just ignore it.  Do not
deny an open request because it is set.

Reviewed-on: http://gerrit.openafs.org/5410
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Tested-by: Jeffrey Altman <jaltman@openafs.org>
(cherry picked from commit 793fdd3360982c48bf60eefbd9c56b4a3c1e09f0)

Change-Id: Ice8758dcbd0b355c9fdfb5af293b6d670ec8c1e4
Reviewed-on: http://gerrit.openafs.org/6037
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>