LU-6081 lfs: fixed bad return value

LU-6081 lfs: fixed bad return value

When a command parameter line is invalid, CMD_HELP should be returned.

Signed-off-by: frank zago <fzago@cray.com>
Change-Id: Icca4886ca2d6497837ea359b3a96398253467e19
Reviewed-on: http://review.whamcloud.com/13293
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: jacques-Charles Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Reviewed-by: Aurelien Degremont <aurelien.degremont@cea.fr>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>