Add metering information from osmo-cc to B-Netz and C-Netz

Untested!

src/fuvst/fuvst.c

@@ -1360,7 +1360,7 @@ int call_down_setup(int callref, const char __attribute__((unused)) *caller_id,
 	return 0;
 }
 
-void call_down_answer(int callref)
+void call_down_answer(int callref, struct timeval __attribute__((unused)) *tv_meter)
 {
 	transaction_t *trans;
 	uint8_t opcode, *data;

src/fuvst/sniffer.c

@@ -263,7 +263,7 @@ void call_down_clock(void) {}
 
 int call_down_setup(int __attribute__((unused)) callref, const char __attribute__((unused)) *caller_id, enum number_type __attribute__((unused)) caller_type, const char __attribute__((unused)) *dialing) { return 0; }
 
-void call_down_answer(int __attribute__((unused)) callref) { }
+void call_down_answer(int __attribute__((unused)) callref, struct timeval __attribute__((unused)) *tv_meter) { }
 
 void call_down_disconnect(int __attribute__((unused)) callref, int __attribute__((unused)) cause) { }