Exit gNB if connection to eNB failed - to be modified if needed.

We may want to try to connect over and over again until we succeed
but the modifications to the code to get this behavior are complex.

Exit on error is a simple solution.

MR !1114 : sanitize v1
-bugs or dirty code fixed 
-add first version of a rf board calibration tool, not finished

MR !1094 : sim channels
Channel simulation: 
-command mode: to change noise, path loss, model (AWGN, RICE, ...) parameters channel simulation 
-channels separation: each channel can have a different model (for HO test for example) 
-a new build option --sanitize to compile all OAI with gcc --sanitize=address

MR !1034 : new gtpu
-New GTPU implementation

MR !1101 : develop-SA-CBRA
-Implementation of Contention Based Random Access procedures for 5G-NR Initial Access in SA mode (including contributions from BUPT and Fujitsu)

 Conflicts:
	openair1/PHY/TOOLS/nr_phy_scope.c
	targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp

 Conflicts:
	cmake_targets/CMakeLists.txt
	openair1/PHY/TOOLS/time_meas.h
	openair2/LAYER2/PDCP_v10.1.0/pdcp_fifo.c
	openair2/LAYER2/RLC/rlc.h

This reverts commit e06c7276

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Integration Branch : 2021 week 14

See merge request oai/openairinterface5g!1121

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Signed-off-by: Mohammed Ismail <mohammed.ismail@openairinterface.org>

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>