LU-303 fix ofed download for bugfix releases

LU-303 fix ofed download for bugfix releases

On the OFED download server both w.x.y and w.x.y.z releases are
stored in the w.x.y dir, so handle that properly for the w.x.y.z case.

Signed-off-by: Brian J. Murrell <brian@whamcloud.com>
Change-Id: Ic0ba6861ce000a9cc47c63219e357d2f6636b951
Reviewed-on: http://review.whamcloud.com/527
Tested-by: Hudson
Reviewed-by: Yang Sheng <ys@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Michael MacDonald <mjmac@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>