LU-10604 osd: define couple fields as bitfield

LU-10604 osd: define couple fields as bitfield

redefine oo_compat_dot_created and oo_compat_dotdot_created
to save 8 bytes per object.

Change-Id: I92dafc693f1d118debc251d7d064b206e36624f0
Signed-off-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-on: https://review.whamcloud.com/31097
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>