LU-1115 kernel: software raid6 related BUG

LU-1115 kernel: software raid6 related BUG

Software raid6 hit BUGON in fs/bio.c:222 when raid chunk > 64k.
We pull upstream patch: 5b99c2ffa980528a197f26c7d876cceeccce8dd5
to deal with this issue.

Signed-off-by: yang sheng <ys@whamcloud.com>
Change-Id: I5330bc161e7cf5364a614547949323fc9a3ee7e3
Reviewed-on: http://review.whamcloud.com/2625
Reviewed-by: Bobi Jam <bobijam@whamcloud.com>
Reviewed-by: Johann Lombardi <johann@whamcloud.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>