LU-5867 lfsck: Enable --create_mdtobj flag

LU-5867 lfsck: Enable --create_mdtobj flag

Using the --create_mdtobj flag in 'lctl lfsck_start'
creates an error. "create_mdtobj" is added to the
option struct so it will be recognized as a valid option.

When displaying the results of LFSCK, "create_mdtobj" is
not listed as a parameter. "create_mdtobj" is added to
the lfsck_param_names array so it will be printed when
used.

Also, added LSV_CREATE_MDTOBJ to the lfsck_request
valid options/flags.

Signed-off-by: James Nunez <james.a.nunez@intel.com>
Change-Id: I1923bb9a71958b390b9abea248b328ac59c3caad
Reviewed-on: http://review.whamcloud.com/12578
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>