T: make number of subframes per frame a configurable item

Think: NR with different number of slots per frame depending on mu.

The name 'subframes_per_frame' is a bit ambiguous. It is valid for LTE,
but for NR it should be 'slots_per_frame'.

For example, for sub-carrier spacing of 30KHz, we have 20 slots per
frame, so in this case subframes_per_frame = 20. In reality whatever
the numerology, there is always 10 subframes per frame in NR.

But how to name this variable which is used both for LTE and NR cases?
'subframes_or_slots_per_frame'? It's a bit long and also ambiguous.

Conclusion: no big deal I think. 'subframes_per_frame' and so be it.

common/utils/T/tracer/logger/logger.h

@@ -16,7 +16,7 @@ logger *new_ticked_ttilog(void *event_handler, void *database,
     int convert_to_dB, float empty_value);
 logger *new_throughputlog(void *event_handler, void *database,
     char *tick_event_name, char *frame_varname, char *subframe_varname,
-    char *event_name, char *data_varname);
+    char *event_name, char *data_varname, int subframes_per_frame);
 logger *new_timelog(void *event_handler, void *database, char *event_name);
 logger *new_ticklog(void *event_handler, void *database,
     char *event_name, char *frame_name, char *subframe_name);