Merge branch 'RU-RAU-split' of https://gitlab.eurecom.fr/oai/openairinterface5g into nfapi-ru-rau-split

Conflicts:
	openair2/RRC/LITE/L2_interface.c
	targets/PROJECTS/GENERIC-LTE-EPC/CONF/enb.band7.tm1.50PRB.usrpb210.conf

Merge branch 'nfapi-ru-rau-split' of https://gitlab.eurecom.fr/daveprice/openairinterface5g into nfapi-ru-rau-split

added configuration file for nFAPI PNF (oaiL1) and modifications in startup procedure to initialize L1 only. When executed, it just waits for configuration, which will never come ... Provides and initial framework to integrate NFAPI PNF modules.

addition of MPDCCH format 5. X_u_br sequences for BL/CE UE support and bugfixes in rx_prach0 for eMTC.

complete programming of Msg2/Msg4 procedures for eMTC. Addition of skeleton for PUCCH UCI (NFAPI) in L1. Some cleanup of eNB_scheduler.c

fixes for RRU/RAU function after changes for monolithic eNB (some things during init were broken for RRU)

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