reworked MNCC codebase

This is Harald's reworked MNCC base, slowly heading towards integration
into master.  The key changes are:
* provide much more structure to the data in gsm_mncc
* encode_* and decode_* functions now take a structure rather than tons
  of individual arguments (whose order nobody can remember)
* make sure we don't have copies of the same code everywhere by introducing
  mncc_set_cause() and mncc_release_ind()
* save horizontal screen space if possible
* make sure we break lines > 80 characters
diff --git a/openbsc/src/vty_interface.c b/openbsc/src/vty_interface.c
index 44531dd..6597e44 100644
--- a/openbsc/src/vty_interface.c
+++ b/openbsc/src/vty_interface.c
@@ -326,6 +326,8 @@
 		vty_out(vty, "  No Subscriber%s", VTY_NEWLINE);
 }
 
+#if 0
+TODO: callref and remote callref of call must be resolved to get gsm_trans object
 static void call_dump_vty(struct vty *vty, struct gsm_call *call)
 {
 	vty_out(vty, "Call Type %u, State %u, Transaction ID %u%s",
@@ -349,6 +351,7 @@
 	} else
 		vty_out(vty, "Call has no Called Subscriber%s", VTY_NEWLINE);
 }
+#endif
 
 DEFUN(show_lchan,
       show_lchan_cmd,