LU-17431 ost: add ioctl handler for oss

LU-17431 ost: add ioctl handler for oss

Adding ioctl handler for oss allows managing dynamic nodemaps
on OSS side.

Test-Parameters: trivial
Signed-off-by: Sebastien Buisson <sbuisson@ddn.com>
Change-Id: I90f4c6988bed2ba721e366ae088983958d484a2f
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54505
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>