1.2.9.final fix bz987259

Without this fix, mod_cluster manager console shows, e.g.:

    Balancer: qacluster,LBGroup: ,Flushpackets: Off,Flushwait: 10000,Ping: 10000000,Smax: 1,Ttl: 60000000,Status: OK,Elected: 0,Read: 0,Transferred: 0,Connected: 0,Load: -1 

note Load: -1. Even if all workers but the hot-standby one are down, balancer won't target the -1 node.

This patch fixes it.