PRB based averaging can activated from command line options

for gNB its in L1 section of config file
for UE its a cmd line paramenter

- skipping RA procedures when MAC is disabled
- added mac_enabled flag that allows to disable RA and TA at UE from CL

- got rid of global variable fp
- code cleanup, removed redundant and unused code
- removed unused command line options and variables
- grouped command line setting in set_options function

This commit contains work done by Eurecom and by Benetel.

ignoring command line paramters clock_source and time_source in lte-softmodem and harmonizing it with nr-softmodem
time_source and clock_source handled separately in usrp_lib.cpp

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

definition of config request fapi structures in UE and acquisition from rrc of config data (work in progress)

 - command line paramter --clock-source can only be set at UE (removed this option from gNB)
 - at gNB use clock_source from RU section in config file
 - in both cases if clock_source is present in usrp_args, it will override clock_source

remove RRC_VERSION macros, simplify build-oai and CMakefile.txt accordingly, get rid of remaining compilation warnings (opt module improperly merged and patch asn1c files with tests against max 64 bits integer value)