vlib: introduce vlib_get_main_by_index(), vlib_get_n_threads()

Type: improvement
Change-Id: If3da7d4338470912f37ff1794620418d928fb77f
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vlibmemory/vlib_api.c b/src/vlibmemory/vlib_api.c
index 51378a5..f033070 100644
--- a/src/vlibmemory/vlib_api.c
+++ b/src/vlibmemory/vlib_api.c
@@ -561,7 +561,7 @@
 void
 vl_api_send_pending_rpc_requests (vlib_main_t * vm)
 {
-  vlib_main_t *vm_global = &vlib_global_main;
+  vlib_main_t *vm_global = vlib_get_first_main ();
 
   ASSERT (vm != vm_global);
 
@@ -576,7 +576,7 @@
 				    u8 force_rpc)
 {
   vl_api_rpc_call_t *mp;
-  vlib_main_t *vm_global = &vlib_global_main;
+  vlib_main_t *vm_global = vlib_get_first_main ();
   vlib_main_t *vm = vlib_get_main ();
 
   /* Main thread and not a forced RPC: call the function directly */