Since we want to use the rootless cni ns also for netavark we should
pick a more generic name. The name is now "rootless network namespace"
or short "rootless netns".
The rename might cause some issues after the update but when the
all containers are restarted or the host is rebooted it should work
correctly.
Signed-off-by: Paul Holzinger <pholzing@redhat.com>