LU-80 lov: large stripe count support

LU-80 lov: large stripe count support

Currently a file can be stripped across OSTs up to a limit of
160 stripes. This patch expands that limit to 2000 and it is
possible to go even to larger stripe counts.

Signed-off-by: Alexander Boyko <alexander_boyko@xyratex.com>
Change-Id: I42e1aad35dd056faac23a0d5b025e0a23fc4ec2f
Reviewed-on: http://review.whamcloud.com/1111
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>