- Fixes bugs #347583, #349389, both of which were triggered by cgroups
being detected as the LXC subsystem type.
- Makes it much easier to select "prefix" type.
- "rc -S" will now print a warning if you have not configured rc_sys in
/etc/rc.conf
- All other semantics of rc_sys are unchanged in this patch.
Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>