ctrl/vty: fsm: use correct element when iterating over fsm->proc.children

Fixes crashes when using vty `show fsm-instances all`
when fsm children are present.

Change-Id: I4ae0bee7f7f57ec6675cfb52ca6cf0d523d15362
diff --git a/src/vty/fsm_vty.c b/src/vty/fsm_vty.c
index 8628d15..9bde241 100644
--- a/src/vty/fsm_vty.c
+++ b/src/vty/fsm_vty.c
@@ -102,7 +102,7 @@
 					    fsmi->proc.parent_term_event),
 			VTY_NEWLINE);
 	}
-	llist_for_each_entry(child, &fsmi->proc.children, list) {
+	llist_for_each_entry(child, &fsmi->proc.children, proc.child) {
 		vty_out(vty, " Child: '%s'%s", child->name, VTY_NEWLINE);
 	}
 }