LU-988 clio: use OSC object's m/a/ctime when build write RPC

LU-988 clio: use OSC object's m/a/ctime when build write RPC

When building OST write RPC, inode's m/a/ctime are out-dated until
lov_merge_lvb() is called, so we need OSC object's m/a/ctime to set
the OST object.

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: Ie4466ad646fd87c36577ea2aad5fa19ad97c5be7
Reviewed-on: http://review.whamcloud.com/3200
Reviewed-by: Jinshan Xiong <jinshan.xiong@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>