LU-1923 lov: verify stripe is on given device

LU-1923 lov: verify stripe is on given device

When restarting FIEMAP from a file with many extents, the first
supplied fiemap extent contains the offset of the previous last
extent found.  If this data is invalid, it may cause the LOV code
to acccess out-of-bounds array indices.

Verify data passed from userspace is within bounds.

Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Change-Id: I8e70e891b9f23c8f72aa78a4807369584ac2b04f
Reviewed-on: http://review.whamcloud.com/3962
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: wangdi <di.wang@whamcloud.com>