- lxc.aa_profile => lxc.apparmor.profile
- lxc.aa_allow_incomplete => lxc.apparmor.allow_incomplete
- lxc.se_context => lxc.selinux.context

The legacy keys will be kept around until LXC 3.0 and then will be removed.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>