Integration 2019 w18

See merge request !582

Merge remote-tracking branch 'origin/Develop-nr-threequarter_fs-80mhz-x310' into integration_2019_w18

The following Merge Requests are included:

* MR 557 : Implement CDRX in FDD mode
* MR 571 : Improvement on documentation
* MR 572 : Fix CU/DU protocol split
* MR 574 : Fix a flexran free issue
* MR 578 : CI -- Improve OAI UE testing with USRP

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>

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

1. Fix code generated from ASN.1 of F1AP v15.4.0 failed to be compiled
2. Fix incorrect UPER encoding for empty extensible SEQUENCE in 38.331
3. Fix the problem that duplicate type names exist in OPEN TYPE

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

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

 --> looping during the initOAIUE stage

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

* Instead of partly initializing in read_config_and_init(), everything of
  PDCP is initialized in main() of lte-softmodem
* Omit RC.rrc access in RRU through checking of RC.nb_inst > 0
* Includes FlexRAN, i.e. do not start FlexRAN in RRU
* Function pointers to PDCP functions have to be set explicitly (avoid
  confusion of multiply setting function pointers)

The changes made in this branch is to enable -E(threequarter sampling rate) option for mu=1 and 217PRB(ie; 80 MHz) to run on USRP x310.

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>

Merge branch '421-cdrx-for-lte' of https://gitlab.eurecom.fr/oai/openairinterface5g into 421-cdrx-for-lte

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