staging/lustre: fix frong ldlm flags type used

Fixed implicit conversion from 'unsigned long long' to 'int'.

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-on: http://review.whamcloud.com/7799
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4023


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>