LU-6017 obd: remove destroy cookie handling

LU-6017 obd: remove destroy cookie handling

Clients no longer need to track the max and default MDS cookiesizes
so remove
  the obsolete obod o_valid flag OBD_MD_FLCOOKIE,
  the struct client_obd members cl_{default,max}_mds_cookiesize,
  the struct obd_trans_info and parameters of this type,
  the get info keys KEY_{DEFAULT,MAX}_COOKIESIZE,
  the cookiesize parameters from md_init_ea_size(),
  the files llite/*/{default,max}_cookiesize, and
  any code that needlessly handled these values.

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I95f0dae370998006ec366a252891db531759ea7d
Reviewed-on: http://review.whamcloud.com/12922
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>