LU-6539 quota: fix incorrect format string used for short type

LU-6539 quota: fix incorrect format string used for short type

The %u in format string requires 'unsigned int' but the argument type
is 'short'.

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Change-Id: Ie84b5f2d46809eb1a840d07ffa0b45f6ada1379e
Reviewed-on: http://review.whamcloud.com/14810
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>