session: cleanup use of api_client_index

Change-Id: I8a680be62ab91d2ccb144641981a635506973a49
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vcl/vcl_cfg.c b/src/vcl/vcl_cfg.c
index 3e92941..402bb91 100644
--- a/src/vcl/vcl_cfg.c
+++ b/src/vcl/vcl_cfg.c
@@ -22,7 +22,7 @@
 static vppcom_main_t _vppcom_main = {
   .debug = VPPCOM_DEBUG_INIT,
   .is_init = 0,
-  .main_api_client_index = ~0,
+  .app_index = ~0,
   .my_client_index = ~0
 };