If we NACK without SOstart/SOend then the other end of the RLC channel will consider all the bytes as NACKed and will have to resend them all. 
If another status is then reported before all the bytes are sent, and because we don't use SOstart/SOend this status will NACK all the bytes again, then all the bytes are to be sent again. 
And the cycle repeats. It will end with a max retx reached (which triggers RLF, Radio Link Failure).

MR1010 : NR UE: Fix for error message - no active DLSCH
- Fixes for the following error message at UE: [PHY] [UE][FATAL] nr_slot_rx 1: no active DLSCH

MR994 : Cleanup softmodem main
- Introduces --dlsch-parallel command line option to set the number of threads for dlsch decoding. If set to 0 (default) no parallelization. 
- Some cleanup in tracing and in nr-uesoftmodem.c data.

MR999 : NR FR2 RA
- Temporary Fix of RA procedure for FR2 (both gNB and UE)
- Fixes in gold sequence initialization at UE
- Moves 2nd downlink to slot 3 instead of 2 to avoid clash with UL DCI (only 1 candidate per slot in FR2 currently)

MR988 : SIB1
Initial implementation of SIB1

 Conflicts:
	openair1/PHY/NR_UE_TRANSPORT/nr_dlsch_decoding.c
	openair2/LAYER2/NR_MAC_UE/nr_ue_dci_configuration.c

Merge branch 'cleanup_softmodem_main' of https://gitlab.eurecom.fr/oai/openairinterface5g into cleanup_softmodem_main

Conflicts:
	openair1/PHY/NR_REFSIG/nr_gold_ue.c

CI: fix flexran-rtc build Xenial

See merge request oai/openairinterface5g!1007

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

 Conflicts:
	openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

MR991: Remove hack in LTE PDCP for noS1 mode  
- Removes a hack which was used when LTE PDCP was used for NR in noS1 mode

MR993: UL and DL fixes LDPC short codewords 
- Fix UL & DL LDPC decoding for short LDPC code, e.g. Z_c is not multiple of 8
- Fix DLSCH data transmission with multiple DMRS symbols per slot
- small TA fixes on OAI 5G NR UE
- Implemented CQI measurement at NR UE
- NR UE cleanup 

MR1000: doc: fix build directory in BASIC_SIM.md