LU-6142 osd-zfs: SPDX for ZFS OSD

LU-6142 osd-zfs: SPDX for ZFS OSD

Convert from verbose license text to SDPX.

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: I02da1c1772da64b88a4469a07d42522472f6ba72
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/55612
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>