* assuming num_dl_slots and num_ul_slots are including also
  slots with dl/ul symbols respectively
* refactor set_tdd_config_nr
* moved function to MAC
* fill max_num_of_symbol_per_slot_list depending on slot type
* use new set_tdd_config_nr in stack
* minor refactor in config.c to improve readability (scs)
Co-authored-by: Guido Casati <guido.casati@firecell.io>

FAPI says these lists should be for MAX_TDD_PERIODICITY (which is maybe
a frame, or a TDD period? but likely not two frames). Reduce to one
frame.

Also, the nFAPI code assumes one entire frame, so use that (this commit
necessary to actually make the PNF work, otherwise, the
packing/unpacking of the FAPI message would need to do 2 frames).

Closes: #876

This commit contains work done by Eurecom and by Benetel.

- replaced nr_slot_t with int as it was barely used in the code (also is defined after an lte struct)
- removed use of phy_frame_config_nr from the UE (another file was created in SCHED_NR_UE, still the
  gNB file is used in some tests file at UE side)