Don't declare success early

Here we're very far from entering the main loop, even farther from
sending the READY notification to systemd. This sounded awkward:

systemd[1]: Starting Corosync Cluster Engine...
corosync[827]: [MAIN ] Corosync Cluster Engine ('2.99.5'):

started and ready to provide service.

corosync[827]: [MAIN ] Corosync built-in features: dbus monitoring

watchdog augeas systemd xmlconf snmp pie relro bindnow

corosync[827]: [MAIN ] parse error in config: No interfaces defined
corosync[827]: [MAIN ] Corosync Cluster Engine exiting with status 8

at main.c:1378.

systemd[1]: corosync.service: Main process exited, code=exited,

status=8/n/a

systemd[1]: corosync.service: Failed with result 'exit-code'.
systemd[1]: Failed to start Corosync Cluster Engine.

Signed-off-by: Ferenc Wágner <wferi@debian.org>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>
Reviewed-by: Christine Caulfield <ccaulfie@redhat.com>