Still a remaining issue with the SNR normalization, way too low to get errors.

0. unwiring of 40 MHz channel hard-coding and general SSB location
1. PSS dynamic range improvement and DC carrier fix
2. SSS channel estimation and detection corrected
3. PBCH channel estimation fixed
4. PBCH channel extraction/compensation reworked for the general case
5. fixed-point low-complexity polar decoder integrated to PBCH decoding chain

works by default (nr_pbchsim) at 100 MHz / 30 kHz SCS and SSB wherever (but known to UE)

Conflicts:
	openair1/PHY/NR_UE_TRANSPORT/nr_initial_sync.c
	openair1/PHY/NR_UE_TRANSPORT/nr_pbch.c
	openair1/PHY/defs_NR.h

Conflicts:
	cmake_targets/CMakeLists.txt
	openair1/PHY/CODING/TESTBENCH/polartest.c
	openair1/PHY/CODING/nrPolar_init.c
	openair1/PHY/CODING/nrPolar_tools/nr_polar_decoder.c
	openair1/PHY/CODING/nrPolar_tools/nr_polar_decoding_tools.c
	openair1/PHY/CODING/nrPolar_tools/nr_polar_defs.h
	openair1/PHY/CODING/nrPolar_tools/nr_polar_rate_match.c
	openair1/PHY/NR_TRANSPORT/nr_pbch.c

Merge branch 'polar-decoder-optimizations' of https://gitlab.eurecom.fr/oai/openairinterface4g into polar-decoder-optimizations

Conflicts:
	openair1/PHY/CODING/nrPolar_tools/nr_polar_defs.h