LU-4629 lmv: fix issue found by Klocwork Insight tool

LU-4629 lmv: fix issue found by Klocwork Insight tool

'plock.cookie' might be used uninitialized in this function.

sscanf format specification '%d' expects type 'int *' for 'd',
but parameter 3 has a different type '__u32*'

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Change-Id: Ie800e69f345e815dc7437b89707cbaabac1af5f7
Reviewed-on: http://review.whamcloud.com/9390
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>