smartd: Don't disable attribute tracking if read thresholds fails.

Windows: Don't return dummy thresholds if IOCTL_STORAGE_QUERY_PROPERTY
or 3ware CLI is used to read SMART data.


git-svn-id: https://smartmontools.svn.sourceforge.net/svnroot/smartmontools/trunk@3039 4ea69e1a-61f1-4043-bf83-b5c94c648137