Add VTY command to specify default speech codec

In order to have the MNCC application reliably decide on the codec type,
it needs to know if we are running on a TCH/F or TCH/H.  Thus, we pass
lchan_mode as a new parameter to the 'struct gsm_mncc'
diff --git a/openbsc/include/openbsc/vty.h b/openbsc/include/openbsc/vty.h
index d455a2b..19b168f 100644
--- a/openbsc/include/openbsc/vty.h
+++ b/openbsc/include/openbsc/vty.h
@@ -35,6 +35,7 @@
 	OM2K_NODE,
 	TRUNK_NODE,
 	PGROUP_NODE,
+	MNCC_INT_NODE,
 };
 
 extern int bsc_vty_is_config_node(struct vty *vty, int node);