dsa: do not dereference non-existing routing table

In the case where there is only one switch, no routing table will have
been allocated, so do not dereference it in this case.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed