This reverts commit 17a1a554.

moved nr_dci_size out of scheduler_phytest

  - Using the implemented DMRS functionalities at the MAC layer at the gNB side
  - Removing is_dmrs_symbol function
  - Temporary implemetation at the UE side considering DMRS symbol is at the 1st PUSCH symbol,
    until the nFAPI structs for DMRS is adopted at the UE side

modifications for DCI size of format 1_0 for RAR and filling of FAPI for RAR according to special RAR-related configuration

added FAPI interfaces int gNB prach receiver functions (rx_nr_prach,rx_nr_prach_ru) and in indication to MAC.

- Updated PRACH procedures and general code formatting
- gNB msg1 handling and RAR generation
- general bug fixing
- formatting
- missing headers
- RAR handling.

nr-ip-UL-nos1: Integrate NR MAC PDU structures for the Uplink. Currently supporting only data SDUs, Control Elements to be added.

scheduling of PUCCH on MAC, passing PUCCH FAPI down to PHY (to be finished), filling DCI structures according to PUCCH (to be finished)