Now that the tree setup is centralized, we can simplify the code a bit
more by setting up or tearing down the tree directly when adding or
removing a switch to/from it.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>