Develop integration 2020 week 25

The following Merge Requests have been included:

* MR 799 : NR RRC PRACH procedures
* MR 831 : NR PUCCH2 polar implementation
* MR 832 : coarse scope cleanup
* MR 835 : fix NR UE transport on PBCH
* MR 836 : NR fix phytest packet corruption DLSCH

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

Merge remote-tracking branch 'origin/nr_fix_phytest_packet_corruption_dlsch' into develop_integration_2020_w25

- Payload was filled with zeros instead of random bytes

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

Develop integration 2020 week 24

The following Merge Requests are included:

* MR 822 : GPU implementation in `ldpctest` unitary test (NCTU)
* A few CI python fixes and to enable back parallel build on RRU
* Documentation update on the supported feature list

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>

Conflicts:
	openair1/PHY/NR_TRANSPORT/pucch_rx.c

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

- Make required adaptations in RLC and default DRB configuration