[IPVS]: Don't leak sysctl tables if the scheduler registration fails.

In case we load lblc or lblcr module we can leak some sysctl
tables if the call to register_ip_vs_scheduler() fails.

I've looked at the register_ip_vs_scheduler() code and saw, that
the only reason to fail is the name collision, so I think that
with some 3rd party schedulers this becomes a relevant issue. No?

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>