L1/L2 scheduling extensions for BL/CE operation, BR random-access procedure, BR PRACH detection. Still untested, but compilation succeeds. Missing elements in L2 - PUSCH programming for Msg3, Msg4 retransmission programming for BL/CE. DLSCH/ULSCH programming for UE-specific DLSCH/ULSCH for BL/CE

Note: this commit is work in progress. Contains initial integration of NFAPI data structures which are tested for TX path. RX path to follow.

those popped up thanks to previous commit

This work was done by Bruno Mongazon.

Prior to this commit, the following command failed to build dlsim:
    ./build_oai --phy_simulators -c

Choice has been made to define it in a .h file as a static inline
function.

The compilation line was:
    ./build_oai --eNB -w USRP

The file openairinterface5g/cmake_targets/log/lte-softmodem.Rel10.txt
has been checked and all LOG_X (and 'msg') warnings have been fixed.

changed the memory allocation of txdataF and beam_weigths

Beamforming is now only done when necessary. This patch is based on one from enhancement-10-harmony.

Some of them might not be correctly handled.
I put /* TODO: XXX */ where I didn't know if
the fix was correct.

fixes for precoding (turning off if nb_antennas_tx=1), configuration files, timing advance with 3/4 sampling on 20 MHz, logging in MAC

bugfix for DCCH2/SRB2 in eNB_scheduler_dlsch.c, demultiplexing SIMD alignment issue in ulsch_decoding.c, IF5 fronthaul modification in lte-enb.c