bridge/br_netlink.c: no need to return void function

br_info_notify is a void function. There is no need to return.

Fixes: b6d0425b ("bridge: cfm: Netlink Notifications.")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>