*: call if_init()/if_terminate() from vrf_init()/vrf_terminate()

Later, an interface will belong to a specific VRF, and the interface
initialization will be a part of the VRF initialization. So now call
if_init() from vrf_init(), and if_terminate() from vrf_terminate().

Daemons have the according changes:
- if if_init() was called or "iflist" was initialized, now call
  vrf_init() instead;
- if if_terminate() was called or "iflist" was destroyed, now call
  vrf_terminate() instead.

Signed-off-by: Feng Lu <lu.feng@6wind.com>
Reviewed-by: Alain Ritoux <alain.ritoux@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vincent JARDIN <vincent.jardin@6wind.com>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/ripngd/ripng_interface.c b/ripngd/ripng_interface.c
index 3588463..c7865d1 100644
--- a/ripngd/ripng_interface.c
+++ b/ripngd/ripng_interface.c
@@ -35,6 +35,7 @@
 #include "table.h"
 #include "thread.h"
 #include "privs.h"
+#include "vrf.h"
 
 #include "ripngd/ripngd.h"
 #include "ripngd/ripng_debug.h"
@@ -1177,7 +1178,6 @@
 ripng_if_init ()
 {
   /* Interface initialize. */
-  iflist = list_new ();
   if_add_hook (IF_NEW_HOOK, ripng_if_new_hook);
   if_add_hook (IF_DELETE_HOOK, ripng_if_delete_hook);