LU-6543 utils: fix memory leak in lfs_setstripe

LU-6543 utils: fix memory leak in lfs_setstripe

Allocated buffer param should be freed before return.

Signed-off-by: Dmitry Eremin <dmitry.eremin@intel.com>
Change-Id: I22d21fb12c0f62330a7c2ca6296f571db71084f2
Reviewed-on: http://review.whamcloud.com/14809
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>