LU-16 Allow objects larger than 2TB in size

LU-16 Allow objects larger than 2TB in size

Use OST superblock sb->s_maxbytes telling LOV the maxmimum object size
it supports, and LOV records the minimum of the per-OSC maxbytes values
to determine the lov_stripe_md.lsm_maxbytes.

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Change-Id: Ice920dc59f5cc5855393bb7031fa089757b3314d
Bugzilla: 20128
Reviewed-on: http://review.whamcloud.com/241
Tested-by: Hudson
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>