relay: fix wrong invocation of router_readconfig
relay: fix wrong invocation of router_readconfig

For some reason queuesize and batchsize were reversed, leading to wrong
numbers internally, but worse, breaking the any_of failover target
(issue #16), since the queue length maths no longer made sense.

grobian/carbon-c-relay,lyft/carbon-c-relay,piotr1212/carbon-c-relay,Skyscanner/carbon-c-relay,lyft/carbon-c-relay,zzl0/carbon-c-relay,Skyscanner/carbon-c-relay,rtoma/carbon-c-relay,grobian/carbon-c-relay,tjamesturner/carbon-c-relay,piotr1212/carbon-c-relay,rtoma/carbon-c-relay,grobian/carbon-c-relay,tjamesturner/carbon-c-relay,piotr1212/carbon-c-relay,zzl0/carbon-c-relay,piotr1212/carbon-c-relay,lyft/carbon-c-relay