LU-715 lov: fix procfs reporting for qos values

LU-715 lov: fix procfs reporting for qos values

When writing to
/proc/fs/lustre/lov/<fsname>-mdtlov/{qos_prio_free,qos_threshold_rr},
the values read back are often one less than the values written.
This happens because internally the value is stored as a number from
0-255 but accessed by the user with 0-100. Integer truncation in the
storage and retrieval stages causes this to often show lower. Adding
255 to an internal step causes the bit-shift to "round up".

Signed-off-by: Matt Ezell <ezell@nics.utk.edu>
Change-Id: I3bb1bb4b048d40eb3882c7cb22799320f90496c7
Reviewed-on: http://review.whamcloud.com/1522
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>