ORBit 0.5.17 CORBA_ORB_perform_work implementation

[Matt Doar <matt trpz com>]

I noticed that the CORBA_ORB_perform_work() function in src/orb/server.c
was marked as "not implemented" in ORBit 0.5.17. I have to integrate
ORBit with a time-sliced C application, so CORBA_run won't work for me.
I've seen the results of searching on perform_work on the mailing list
for the last two years.

The following suspiciously simple two line fix seemed to implement it. 
Would anyone care to glance at it and comment on its correctness?

~Matt

/* Section 4.9.2 */
void CORBA_ORB_perform_work(CORBA_ORB orb, CORBA_Environment *ev)
{
	ORBit_custom_run_setup(orb, ev);
	giop_main_iterate(FALSE);
}