LU-6047 obd: remove client Size on MDS support

LU-6047 obd: remove client Size on MDS support

Remove the unused OBD MD API method md_done_writing(). Remove the
unused logcookie and struct md_open_data ** parameters from
md_setattr(). Remove the unused functions iattr_from_obdo(),
md_from_obdo(), and obdo_refresh_inode().

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Change-Id: I59bf2b101807f5b582eb7ab27e5a742284800979
Reviewed-on: http://review.whamcloud.com/13169
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Henri Doreau <henri.doreau@cea.fr>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>