Call breakpoint_on_hit for return breakpoints as well

- This was always supposed to happen, but did not by omission.
diff --git a/handle_event.c b/handle_event.c
index 3b45e9c..ec8713e 100644
--- a/handle_event.c
+++ b/handle_event.c
@@ -796,6 +796,7 @@
 		struct breakpoint *bp
 			= address2bpstruct(proc->leader, elem->return_addr);
 		if (bp != NULL) {
+			breakpoint_on_hit(bp, proc);
 			delete_breakpoint(proc, bp);
 		}
 	}