staging/lustre/obdclass: Fix uninitialized variables

'sd.page_link' is used uninitialized in this function.
'ss.page_link' is used uninitialized in this function.
'sl.page_link' is used uninitialized in this function.

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: http://review.whamcloud.com/10613
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4629


Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>