LU-8915 lnet: migrate LNet selftest group handling to Netlink

LU-8915 lnet: migrate LNet selftest group handling to Netlink

Replace the LSTIO_GROUP_LIST and LSTIO_GROUP_INFO ioctls with a Netlink
backend. Make this transitition transparent to the user. Be aware this
newer version of lnet_selftest.ko doesn't support older versions of the
lst tool. While the old interface allows only setting one group up at
a time the Netlink interface can be used to setup many groups at one
time. Currently we don't change the interface to handle larger NIDs but
this new interface will allow us to use the new NID format in a follow
on patch.

Change-Id: I18f07b380d353425c6e127e4fbd0f30e41f66944
Test-Parameters: trivial testlist=lnet-selftest
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/49314
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov@whamcloud.com>
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>