tdef_vty: do not enforce enum 'node_type' in osmo_tdef_vty_groups_init()

Some osmo-* applications may need to use their own VTY node as a
parent for the timer configuration commands. Therefore it makes
more sense to use 'unsigned int' instead of 'enum node_type'.

Let's also clarify that osmo_tdef_vty_groups_init() accepts parent
node for configuration commands only: 'parent_node' -> 'parent_cfg_node'.

Change-Id: Ifb4c406c85d76a25fc53fc235484599aa87dc77c
diff --git a/include/osmocom/vty/tdef_vty.h b/include/osmocom/vty/tdef_vty.h
index 6334d5b..800af7d 100644
--- a/include/osmocom/vty/tdef_vty.h
+++ b/include/osmocom/vty/tdef_vty.h
@@ -68,7 +68,7 @@
 struct osmo_tdef *osmo_tdef_vty_parse_T_arg(struct vty *vty, struct osmo_tdef *tdefs, const char *osmo_tdef_str);
 unsigned long osmo_tdef_vty_parse_val_arg(const char *val_arg, unsigned long default_val);
 
-void osmo_tdef_vty_groups_init(enum node_type parent_node, struct osmo_tdef_group *groups);
+void osmo_tdef_vty_groups_init(unsigned int parent_cfg_node, struct osmo_tdef_group *groups);
 void osmo_tdef_vty_groups_write(struct vty *vty, const char *indent);
 
 /*! @} */