freetdm: use s<spanno>c<channo> notation for logging channel related msgs

libs/freetdm/src/include/private/ftdm_core.h

@@ -561,8 +561,8 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_open_chan(ftdm_channel_t *ftdmchan);
 
 #define ftdm_channel_lock(chan) ftdm_mutex_lock(chan->mutex)
 #define ftdm_channel_unlock(chan) ftdm_mutex_unlock(chan->mutex)
-#define ftdm_log_chan(fchan, level, format, ...) ftdm_log(level, "%d:%d " format, fchan->span_id, fchan->chan_id, __VA_ARGS__)
-#define ftdm_log_chan_msg(fchan, level, msg) ftdm_log(level, "%d:%d " msg, fchan->span_id, fchan->chan_id)
+#define ftdm_log_chan(fchan, level, format, ...) ftdm_log(level, "s%dc%d " format, fchan->span_id, fchan->chan_id, __VA_ARGS__)
+#define ftdm_log_chan_msg(fchan, level, msg) ftdm_log(level, "s%dc%d " msg, fchan->span_id, fchan->chan_id)
 
 static __inline__ void ftdm_abort(void)
 {