ipvs: failed RS was flapping on config reload

The RS disabled by health-checker was turned on w/o health-checking
by SIGHUP handler in the init_service_rs() subroutine.
This did not happen with alpha mode set.

The issue was reported by Luis Fernando Cornachioni Estrozi
in the keepalived-devel@ list.
Merge pull request #106 from andriyanov/to_acassen

ipvs: failed RS was flapping on config reload